FUSION APPARATUS AND METHODS Priority The present application claims priority to U. S. Provisional Patent Serial No.

60/478,699, entitled"Fusion Apparatus And Methods"filed June 13, 2003, and U. S. Serial No. 10/of the same title, filed June 10,2004, both incorporated herein by reference in their entirety.

Background of the Invention 1. Field of the Invention The present invention relates generally to physics, and particularly to, inter alia, improved apparatus and methods for producing and harnessing nuclear fusion.

2. Description of Related Technology Nuclear fusion is a well understood process whereby, in one exemplary configuration, light (low-Z) atomic species are"fused"so as to form a heavier species, such as where two Hydrogen (H) isotopes are fused to form Helium (He) atoms. The Hydrogen bomb is one example of a large-scale (largely uncontrolled) fusion reaction, as is the sun.

The benefits of fusion energy include: (i) much energy with abundant hydrogen fuel ; (ii) safe operations with no potential for uncontrolled chain reactions; (iii) little and short- lived radioactive waste; and (iv) little or no environmental impact.

Control of such fusion reactions, however, has proven elusive. Numerous different approaches to creating and sustaining a fusion reaction have been proffered over time, yet none have provided both the desired degree of productive energy output (especially in comparison to energy input to create and sustain the reaction for any appreciable period of time) and level of practicality or cost-efficiency which would permit wide-spread use of fusion technology. A variety of technological challenges are presented in attempting to harness fusion, which can exceed temperatures of I E08 F. As such temperatures, literally any known material will cease to exist in its original form (e. g. , dissociate), and even fundamental magnetic and electric field properties can be altered. Magnetic containment approaches such as the well-known Tokamak (discussed below) and Spheromak have all been only marginally successful at even generating a fusion event, let alone sustaining one for any appreciable period of time, or even remotely approaching a practical implementation in terms of size, cost, or most importantly energy balance (i. e. , energy in versus energy out). Similar limited results have been obtained by high-energy laser- pumped solutions such as those used by Lawrence Livermore National Laboratories (LLNL), and the so-called"Z-pinch"fusion accelerator device of Sandia National Laboratories. Particular aspects of these approaches are described subsequently herein.

Starting in the early 1990s, fusion research took a new direction by using physically large, high power lasers to ignite the reactions. Two of the most powerful and costly lasers systems, "Shiva"and"Nova"were developed at the Lawrence Livermore National Laboratory (LLNL). The larges, Nova, is as long as a football field and three stories high. It uses ten lasers focused onto a 1 mm diameter fuel target, and has produced peak powers of 10'4 watts. In 1994, Nova reached the Lawson criterion for net energy production fusion (see discussion below), but at a temperature too low for fusion ignition.

In 1999, the laser approach produced a major milestone (per T. Ditmire et al at the Lawrence Livermore National Laboratory, and G. Mourou at the University of Michigan).

New, femto-second lasers, producing peak powers on the order of 1016 to 102° watts/cm2, created nuclear fusion from explosions of laser heated deuterium clusters, in times less than 35 femto-seconds. These were, in a real sense, sub-micron sized hydrogen bombs. The fusions of sub-micron sized deuterium clusters were produced with Titanium-Sapphire lasers that could fit onto a table top. The by-products of the reactions include 2.45 MeV neutrons and energetic, charged alpha particles (nuclei of Helium). The process has been named"table top fusion".

The reactors for creating controlled nuclear fusion have generally been of two main varieties. These are the magnetic confinement reactor and the inertial confinement reactor.

Magnetic confinement reactors confine the hot fusion plasmas by magnetic fields.

These fields keep the plasma particles perpetually looping in circles and helical paths around magnetic field lines, and are typified by the Russian tokamak design. Examples of this approach are the TFTR (Tokamak Fusion Test Reactor) at Princeton Plasma Physics Laboratory, and the tokamak at General Atomics Corporation in La Jolla, CA. In essence, magnetic forces on the plasma particles keep them away from the walls of the containment.

In inertial confinement, the strategy is to put extremely high energy density beams (as from lasers) into a small pellet of fuel such as deuterium, or a mixture of deuterium and tritium, over very short temporal durations. This causes nuclear fusion in the material, in a short enough time so that the fuel pellets cannot move appreciably. Here, "short duration" refers to reaction times less than 50 femto-seconds (50 x 10-15 sec). This was the approach used by Lawrence Livermore in 1999, with the aforementioned femto-second laser. This approach has significant utility, although laser confinement also plays a role.

Confinement is necessary to keep the hot plasmas from touching the walls of the containers. The walls can be destroyed by the plasma, and in turn, they can quench the nuclear reactions. The plasma temperatures involved are typically 50-100 million degrees Kelvin, which are too high to be contained by any known material.

In the current state-of-the-art fusion reactor designs, the neutrally charged, fusion neutrons will be absorbed in a boiler to heat water. The resulting steam powers a conventional turbine electric generator. The charged alpha particles from the fusion reactions stay within the plasma, and will be used to-self-heat the plasma to even higher temperatures.

The following references are representative of the prior art in various disciplines of nuclear fusion technology, each of the following references being incorporated herein by reference in its entirety.

U. S. Patent No. 3,940, 617 to Farnum, et al. issued February 24,1976 entitled "Method for nondestructive fuel assay of laser fusion targets"discloses a method for nondestructively determining the deuterium and tritium content of laser fusion targets by counting the X-rays produced by the interaction of tritium beta particles with the walls of the micro-balloons used to contain the deuterium and tritium gas mixture under high pressure. The x rays provide a direct measure of the tritium content and a means for calculating the deuterium content using the initial known D-T ratio and the known deuterium and tritium diffusion rates.

U. S. Patent No. 3,946, 240 to Roberts, et al. issued March 23,1976 entitled "Energetic electron beam assisted fusion neutron generator"discloses an energetic electron beam fusion neutron generator in which a plasma is induced by a plasma generator to produce neutrons and to increase the number of neutrons produced, an electron source is guided to the produced plasma to further heat the plasma and produce an even greater number of neutrons. The inner electrode of the plasma generator utilizes the interaction of the beams self magnetic field with the inner surface of the inner electrode to guide the electron source to the plasma.

U. S. Patent No. 3,959, 659 to Roberts, et al. issued May 25,1976 entitled"Intense, energetic electron beam assisted fusion neutron generator"discloses an energetic electron beam assisted fusion neutron generator which comprises a plasma generator and an electron source interconnected by a pinch tube and control means for the plasma generator, electron source, and pinch tube to cause the electron source to be focused on the plasma from the plasma generator and to cause the electron source to be transmitted to the plasma of the plasma generator at the appropriate time to cause a maximum amount of neutrons to be produced by the interaction of the outputs of the plasma generator and the electron source through an appropriate gas filling the plasma generator.

U. S. Patent No. 3,991, 309 to Hauer issued November 9,1976 entitled"Methods and apparatus for the control and analysis of X-rays"discloses a fast X-ray excitation processes such as occur during nuclear fusion reactions where high energy laser pulses hit a target, as for the purpose of stimulating atomic emission, may be analyzed by interposing a crystal in the path of the X-rays. The X-rays are transmitted through this crystal by means of the anomalous transmission or Bormann effect. A periodic strain field is established in the crystal to enable or inhibit anomalous transmission.

U. S. Patent No. 3,997, 435 to Farnum, et al. issued December 14, 1976 entitled "Method for selecting hollow microspheres for use in laser fusion targets"discloses hollow microspheres having thin and very uniform wall thickness useful as containers for the deuterium and tritium gas mixture used as a fuel in laser fusion targets. Hollow microspheres meeting requirements may be separated from the unsuitable ones by subjecting the commercial lot to size and density separations and then by subjecting those hollow microspheres thus separated to an external pressurization at which those which are spherical or which have nonuniform walls are broken and separating the sound hollow spheres from the broken ones.

U. S. Patent No. 4,000, 036 to Ensley issued December 28, 1976 entitled"Plasma control and utilization"discloses a plasma is confined and heated by a microwave field resonant in a cavity excited in a combination of the TE and TM modes while responding to the resonant frequency of the cavity as the plasma dimensions change to maintain operation at resonance. The microwave field is elliptically or circularly polarized as to prevent the electromagnetic confining field from going to zero. A high Q chamber having superconductive walls is employed to minimize wall losses while providing for extraction of thermonuclear energy produced by fusion of nuclei in the plasma.

U. S. Patent No. 4,017, 290 to Budrick, et al. issued April 12,1977 entitled"Method and apparatus for making uniform pellets for fusion reactors"discloses a method and apparatus for making uniform pellets for laser driven fusion reactors which comprises selection of a quantity of glass frit which has been accurately classified as to size within a few microns and contains an occluded material which gasifies and expands when heated.

U. S. Patent No. 4,021, 253 to Budrick, et al. issued May 3,1977 entitled"Method for manufacturing glass frit"discloses a method of manufacturing a glass frit for use in the manufacture of uniform glass microspheres to serve as containers for laser fusion fuel to be exposed to laser energy which includes the formation of a glass gel which is then dried, pulverized, and very accurately sized to particles in a range of, e. g. , 125 to 149 microns.

U. S. Patent No. 4,021, 280 to Rinde, et al. issued May 3,1977 entitled"Method of making foam-encapsulated laser targets"discloses foam-encapsulated laser fusion targets fabricated by suspending fusion fuel filled shells in a solution of cellulose acetate, extruding the suspension through a small orifice into a bath of ice water, soaking the thus formed shell containing cellulose acetate gel in the water to extract impurities, freezing the gel, and thereafter freeze-drying wherein water and solvents sublime and the gel structure solidifies into a low-density microcellular foam containing encapsulated fuel-filled shells.

U. S. Patent No. 4,034, 032 to Hendricks issued July 5,1977 entitled"Method for foam encapsulating laser targets"discloses foam encapsulated laser fusion targets made by positioning a fusion fuel-filled sphere within a mold cavity of suitable configuration and dimensions, and then filling the cavity with a material capable of producing a low density, microcellular foam, such as cellulose acetate dissolved in an acetone-based solvent. The mold assembly is dipped into an ice water bath to gel the material and thereafter soaked in the water bath to leach out undesired components, after which the gel is frozen, then freeze- dried wherein water and solvents sublime and the gel structure solidifies into a low-density microcellular foam, thereafter the resulting foam encapsulated target is removed from the mold cavity. The fuel-filled sphere is surrounded by foam having a thickness of about 10 to 100 micron, a cell size of less than 2 micron, and density of 0.065 to 0. 6E03 kg/m3.

U. S. Patent No. 4,052, 999 to Coultas issued October 11, 1977 entitled"Bumper wall for plasma device"discloses an improved bumper wall enclosing the plasma in a fusion device to smooth the flow of energy from the plasma as the energy impinges upon the bumper wall. The bumper wall is flexible to withstand unequal and severe thermal shocks and it is readily replaced at less expense than the cost of replacing structural material in the first wall and blanket that surround it.

U. S. Patent No. 4, 057, 462 to Jassby, et al. issued November 8,1977 entitled"Radio frequency sustained ion energy"discloses an electromagnetic (E. M. ) energy injection method and apparatus for producing and sustaining suprathermal ordered ions in a neutral, two-ion-species, toroidal, bulk equilibrium plasma. More particularly, the ions are produced and sustained in an ordered suprathermal state of existence above the average energy and velocity of the bulk equilibrium plasma by resonant RF energy injection in resonance with the natural frequency of one of the ion species.

U. S. Patent No. 4,058, 486 to Mallozzi, et al. issued November 15,1977 entitled "Producing X-rays"discloses a method of producing X-rays by directing radiant energy from a laser onto a target. Conversion efficiency of at least about 3 percent is obtained by providing the radiant energy in a low-power precursor pulse of approximately uniform effective intensity focused onto the surface of the target for about 1 to 30 nanoseconds so as to generate an expanding unconfined coronal plasma having less than normal solid density throughout and comprising a low-density (underdense) region wherein the plasma frequency is less than the laser radiation frequency and a higher-density (overdense) region wherein the plasma frequency is greater than the laser radiation frequency and, about 1 to 30 nanoseconds after the precursor pulse strikes the target, a higher-power main pulse focused onto the plasma for about 10-3 to 30 nanoseconds and having such power density and total energy that the radiant energy is absorbed in the underdense region and conducted into the overdense region to heat it and thus to produce X-rays therefrom with the plasma remaining substantially below normal solid density.

U. S. Patent No. 4,076, 990 to Hendry, et al. issued February 28,1978 entitled"Tube target for fusion neutron generator"discloses a target for a fusion neutron generator consisting of planar arrays of parallel tubes through which a cooling liquid is circulated.

The target is relatively thin, and can be used to intercept two ion beams simultaneously, one on the front and the other on the back of the target. Two mixed ion beams, each containing a mixture of deuterium and tritium ions are accelerated into both sides of the water-cooled chromium plated copper-tube target whereby reactions occur yielding 14 MeV neutrons. At typical operating conditions of 170 keV and 300 mA total beam current, the neutron yield with a mixture of deuterium and tritium gas is approximately 6E12 n/sec for an effective beam spot of 5.5 centimeters diameter.

U. S. Patent No. 4, 133, 854 to Hendricks issued January 9,1979 entitled"Method for producing small hollow spheres"discloses a method for producing small hollow spheres of glass, metal or plastic, wherein the sphere material is mixed with or contains as part of the composition a blowing agent which decomposes at high temperature. As the temperature is quickly raised, the blowing agent decomposes and the resulting gas expands from within, thus forming a hollow sphere of controllable thickness. The thus produced hollow spheres (20 to 10E03 micron) have a variety of application, and are particularly useful in the fabrication of targets for laser implosion such as neutron sources, laser fusion physics studies, and laser initiated fusion power plants.

U. S. Patent No. 4, 140, 601 to Gomberg issued February 20,1979 entitled"Multi- step chemical and radiation process"discloses a process which utilizes radiation energy, preferably that obtained from a fusion reaction and which includes selecting starting chemical materials having at least two molecules such as calcium bromide and water which contain as a part thereof a desired product H2, a by-product 02 and which chemically form an active material HBr that may be dissociated by radiation. A two-step process permits the radiolytically dissociated Br to react with residual molecules to form and recycle the starting material CaBr2.

U. S. Patent No. 4, 142, 088 to Hirsch issued February 27, 1979 entitled"Method of mounting a fuel pellet in a laser-excited fusion reactor"discloses laser irradiation means for irradiating a target, wherein a single laser light beam from a source and a mirror close to the target are used with aperture means for directing laser light to interact with the target over a broad area of the surface, and for protecting the laser light source.

U. S. Patent No. 4,145, 250 to Ohkawa, et al. issued March 20, 1979 entitled"In situ regeneration of the first wall of a deuterium-tritium fusion device"discloses apparatus wherein the first wall of a deuterium-tritium fusion reactor is regenerated in situ. The first wall substantially surrounds an enclosed reaction region confined within the reaction chamber of the reactor. To regenerate a worn first wall without opening the reactor chamber, a gaseous substance is introduced into the chamber, at least a portion of the gaseous substance comprising material, such as low Z refractory material, suitable for forming the first wall. At least a portion of this material is deposited, as by pyrolysis, in solid form on the first wall to regenerate the first wall, and residual gas is removed from the chamber. The chamber is then recharged with a mixture of deuterium and tritium.

U. S. Patent No. 4, 149, 931 to Christensen issued April 17, 1979 entitled"Divertor for use in fusion reactors"discloses a poloidal divertor for a toroidal plasma column ring having a set of poloidal coils co-axial with the plasma ring for providing a space for a thick shielding blanket close to the plasma along the entire length of the plasma ring cross section and all the way around the axis of rotation of the plasma ring. The poloidal coils of this invention also provide a stagnation point on the inside of the toroidal plasma column ring, gently curving field lines for vertical stability, an initial plasma current, and the shaping of the field lines of a separatrix up and around the shielding blanket.

U. S. Patent No. 4,172, 008 to Fleet issued October 23,1979 entitled"Nuclear fusion reactor"discloses a rapidly pulsed nuclear fusion reaction system including a firing chamber into which synchronized opposing beams of ionized gas such as deuterium/tritium are injected in the form of ion pulses which are adapted to collide at the mid point of the chamber. The pulsed ion beams are fed through respective orifices across which is applied a relatively high DC voltage. External to the firing chamber is means for generating a pulsed magnetic field interiorally of the chamber along the ion travel path and in synchronism therewith to provide a guiding effect of the two opposing ion beams to the precise center of the firing chamber. At the moment the leading edges of the ion beams meet, an electric arc is developed due to the voltage applied across the orifice.

U. S. Patent No. 4, 182, 650 to Fischer issued January 8, 1980 entitled"Pulsed nuclear fusion reactor"discloses an invention relates to a nuclear fusion power plant for producing useful electrical energy by nuclear combustion of deuterium and lithium to helium. A large concentric plate capacitor is discharged rapidly through a mass of molten LiD-x Tx (O<X<I) that is situated at its center. Before this discharge, a conducting path had been thermally preformed between the electrodes by an ac current pulse. The high-temperature, high-pressure plasma is confined by the LiD liquid in a narrow channel. Neutrons are generated, partly by thermonuclear fusion, partly by suprathermal collisions which result from the well-known sausage instability. Short Li-D-T chain reactions, enhanced by the beryllium content of the electrodes, are also present. The escaping neutrons are absorbed by the surrounding liquid where they breed T, which is then chemically bound, and produce heat. The heat, radiation and mechanical shock are absorbed in the liquid which flows through a heat exchanger in order to energize the associated turbogenerator power plant.

After each pulse, the discharge channel vanishes and is homogenized in the liquid.

U. S. Patent No. 4, 182, 651 to Fischer issued January 8,1980 entitled"Pulsed deuterium lithium nuclear reactor"discloses a nuclear reactor that burns hydrogen bomb material 6-lithium deuterotritide to helium in successive microexplosions which are ignited electrically and enclosed by this same molten material, and that permits the conversion of the reaction heat into useful electrical power. A specially-constructed high-current pulse machine is discharged via a thermally-preformed highly conducting path through a mass of the molten salt 6LiDI-x Tx (0<x<1). In the resulting dense, hot plasma filament primary nucleons are formed by field-accelerated fusion collisions. These hot particles initiate suprathermal multistepped propagating fission-fusion avalanches that heat the plasma by their own released energy up to thermonuclear temperature. The plasma is confined inertially and magnetically. Neutrons escaping sideways are utilized to breed tritium in the surrounding liquid blanket material, for participation in the next pulse.

U. S. Patent No. 4,188, 532 to Deckman, et al. issued February 12,1980 entitled "Method for the non-destructive assaying of laser fusion targets"discloses methods for assay of the tritium fuel content in laser fusion targets and/or to measure the pressurization of laser fusion targets of the type which use deuterium and tritium (DT) gas mixtures, without destroying the targets. The flux of beta particles which emerges from the target is measured with the aid of a gas flow proportional counter. The count rates are related to the tritium content and the pressurization. The tritium content in terms of the mass of the tritium in the target can be derived from the counting rate.

U. S. Patent No. 4,189, 346 to Jarnagin issued February 19,1980 entitled "Operationally confined nuclear fusion system"discloses a system for generating clean controllable inexpensive electrical power by nuclear fusion of light weight atoms and/or isotopes of hydrogen such as deuterium. Fusionable ions are accelerated head-on from many directions through the middle of a reaction chamber. Such ions are produced by especially designed cyclotrons aimed at one another. Since the orbital motion and escape velocity of an ion is controlled by the magnetic field of its originating cyclotron, said ion cannot hit the outer wall of the opposite magnet (which is of equal strength). Hence the system's plasma is operationally contained. The system can produce plasmas of practically any desired average velocity hence temperature; and in densities approaching 1020 per cc at the center of the reaction chamber.

U. S. Patent No. 4,199, 402 to Ahmed issued April 22,1980 entitled"Plasma energy production"discloses energy production by generating an ion stream by laser energy and injecting the ions within a closed loop accelerator. Numerous nodes about the path of the accelerator densify the ions at minimum cross-sections causing substantial kinetic pressure from particles which are accelerated into the nodes together with injected electrons to form a plasma. The accelerator path contains the ions preventing their escape into the atmosphere. The accelerator recycles the ions continuously within the closed loop path for repeated fusion reaction at the nodes.

U. S. Patent No. 4, 216, 058 to Marwick issued August 5, 1980 entitled"Enhanced fission breeder reactor"discloses a large inertial confinement breeder reactor wherein neutron bursts produced by fusion, fission or combined fission and fusion are contained seriatim in a large chamber. Each burst results from interception of a large, sub-critical free- falling mass by a smaller upward accelerated slug such that the combined assembly is more than prompt-critical. The resulting thermal energy is absorbed by a spray which generally fills the chamber. The innermost portion of the spray comprises a dense slurry of actinides in molten sodium while the outer portions of spray comprise a very dilute slurry of actinides in molten sodium. The collected heated spray also contains the debris of the explosion and travels through a heat exchanger-precipitator means wherefrom dense slurry, lean slurry, precipitate, and thermal energy may be extracted.

U. S. Patent No. 4,217, 172 to Mori, et al. issued August 12,1980 entitled"Coolant system and cooling method utilizing two-phase flow for nuclear fusion reactor"discloses a coolant system and cooling method for a neutron generating reactor, wherein the gas helium is blown in the form of bubbles into the liquid coolant such as liquid metallic lithium in the liquid coolant blanket, thereby removing heat from the liquid coolant.

U. S. Patent No. 4,224, 261 to Halpern issued September 23,1980 entitled"Methods of fabricating microsponge deuterated initiated hydrocarbon polymer target which emit neutrons when irradiated by high energy beams"discloses targets for high energy beams, such as laser beams, produced in laser fusion apparatus. The targets are porous spheres of deuterated hydrocarbon material, particularly deuterated polyethylene. The spheres are small and have diameters in the range of 50 to 300 microns. Higher neutron yields are obtained from these targets than from solid targets of similar materials, (viz., spherical targets of much higher density). Methods of fabricating the targets by forming them into solid spheres, cross linking their molecules and causing them to swell such that the resultant targets have a microscopically small sponge-like structure, are also described.

U. S. Patent No. 4,240, 873 to Linlor issued December 23,1980 entitled"Solenoidal fusion system"discloses apparatus and methods to produce nuclear fusion utilizing fusible material in the form of high energy ion beams confined in magnetic fields. For example, beams of deuterons and tritons are injected in the same direction relative to the axis of a vacuum chamber. The ion beams are confined by the magnetic fields of long solenoids. The products of the fusion reactions, such as neutrons and alpha particles, escape to the wall surrounding the vacuum chamber, producing heat. The momentum of the deuterons is approximately equal to the momentum of the tritons, so that both types of ions follow the same path in the confining magnetic field. The velocity of the deuteron is sufficiently greater than the velocity of the triton so that overtaking collisions occur at a relative velocity which produces a high fusion reaction cross section.

U. S. Patent No. 4,244, 782 to Dow issued January 13,1981 entitled"Nuclear fusion system"discloses the method and apparatus for the confining of a stream of fusible positive ions at values of density and high average kinetic energy, primarily of tightly looping motions, to produce nuclear fusion at a useful rate ; more or less intimately mixed with the fusible ions will be lower-energy electrons at about equal density, introduced solely for the purpose of neutralizing the positive space charge of the ions.

U. S. Patent No. 4,246, 067 to Linlor issued January 20,1981 entitled "Thermonuclear fusion system"discloses apparatus and methods to produce nuclear fusion utilizing fusible material in the form of high energy ion beams confined in magnetic fields.

For example, beams of deuterons and tritons are injected in the same direction relative to the machine axis, but the deuteron velocity is sufficiently greater than the triton velocity so that the deuterons overtake the tritons at a relative velocity which produces a high fusion reaction cross section. The momentum of the deuterons is approximately equal to the momentum of the tritons so that both types of ions follow essentially the same path. Thus, the deuteron and triton beams, together with electrons for space charge neutralization, constitute a"moving-plasma", in which fusion reactions occur.

U. S. Patent 4,266, 506 to Miller issued May 12,1981 entitled"Apparatus for producing cryogenic inertially driven fusion targets"discloses a technique for producing uniform layers of solid DT on micro-balloon surfaces. Local heating of the target, typically by means of a focused laser, within an isothermal freezing cell containing a low pressure cryogenic exchange gas such as helium, vaporizes the DT fuel contained within the microballoon. Removal of the laser heating source causes the DT gas to rapidly condense and freeze in a layer which exhibits a good degree of uniformity.

U. S. Patent No. 4,290, 848 to Sudan issued September 22,1981 entitled"Ion-ring ignitor for inertial fusion"discloses apparatus is disclosed for inertial fusion in which a pulse of ions is injected into a magnetic mirror where the ions are trapped in the form of an ion ring which is then magnetically compressed to increase its energy and reduce its dimensions. The compressed ion ring is then accelerated through a guide tube to strike a pellet in a thermonuclear fusion reactor.

U. S. Patent No. 4,297, 165 to Breuckner issued October 27,1981 entitled"Fuel pellets for controlled nuclear fusion"discloses, in connection with a fusion process which can be initiated by a high energy input such as a laser beam, the use of a layer of uranium surrounding the fusion fuel such as deuterium-tritium or a non-cryogenic fuel such as lithium deuterium-lithium tritium. The uranium serves as a tamper layer to contain the fusion fuel and supplement the heating by a fission reaction which not only increases the fusion yield but increases the time of disassembly.

U. S. Patent No. 4,298, 798 to Huffman issued November 3,1981 entitled"Method and apparatus for producing negative ions"discloses a method and apparatus are described for producing negative deuterium ions for use in controlled thermonuclear reactions such as fusion. Negative ions are obtained by bombarding the surface of an ionization electrode with positive ions and extracting negative ions from the electrode. The unique surface layer of the electrode is formed by depositing onto a substrate the products of thermal decomposition of cesium carbonate. This layer, which is easily formed and renewed, is characterized by a very low value of work function of about 1. 05 electron volts.

U. S. Patent No. 4,304, 627 to Lewis issued December 8,1981 entitled"Expandable chamber fusion reactor system"discloses a piston is moved by a laser incited fusion reaction such as deuterium-tritium (D-T) to thereby produce an expandable fusion chamber.

When a gaseous substance such as CO2 is presented in the presence of the fusion reaction, it is dissociated into CO and 02 component mixture and the expansion of the chamber rapidly cools the mixture and quenches the back reaction thereby producing a greater CO yield.

Also the piston produces power from the fusion reaction in the form of mechanical energy.

U. S. Patent No. 4,304, 645 to Pierini issued December 8,1981 entitled"Process for removing helium and other impurities from a mixture containing deuterium and tritium, and a deuterium/tritium mixture when purified in accordance with such a process"discloses a process for removing helium and other impurities from a mixture containing deuterium and tritium. The method comprises: separating from the mixture isotopes of hydrogen in any of their diatomic combined forms; oxidizing the separated isotopes to their corresponding oxides; separating tritium oxide and deuterium-tritium oxide from the oxides thus formed; and electrolyzing the separated oxides to deuterium and tritium. Preferably the impure mixture of deuterium and tritium is a waste product of a fusion reactor, and the purified deuterium/tritium mixture is recycled to the reactor.

U. S. Patent No. 4,314, 879 to Hartman, et al. issued February 9,1982 entitled "Production of field-reversed mirror plasma with a coaxial plasma gun"discloses the use of a coaxial plasma gun to produce a plasma ring which is directed into a magnetic field so as to form a field-reversed plasma confined in a magnetic mirror. Plasma thus produced may be used as a target for subsequent neutral beam injection or other similarly produced and projected plasma rings or for direct fusion energy release in a pulsed mode.

U. S. Patent No. 4,323, 420 to Masnari, et al. issued April 6, 1982 entitled"Process for manufacture of inertial confinement fusion targets and resulting product"discloses an ICF target comprising a spherical pellet of fusion fuel surrounded by a concentric shell ; and a process for manufacturing the same which includes the steps of forming hemispheric shells of a silicon or other substrate material, adhering the shell segments to each other with a fuel pellet contained concentrically therein, then separating the individual targets from the parent substrate.

U. S. Patent No. 4,333, 796 to Flynn issued June 8,1982 entitled"Method of generating energy by acoustically induced cavitation fusion and reactor therefor"discloses two different cavitation fusion reactors (CFR's). Each comprises a chamber containing a liquid (host) metal such as lithium or an alloy thereof. Acoustical horns in the chamber walls operate to vary the ambient pressure in the liquid metal, creating therein small bubbles which are caused to grow to maximum sizes and then collapse violently in two steps.

U. S. Patent No. 4,342, 720 to Wells issued August 3,1982 entitled"Method and apparatus for generation of thermonuclear power"discloses a thermonuclear fusion reactor assembly consisting of a plurality of TRISOPS theta pinch units arranged in a parallel configuration inside a common magnetic guide field and provided with a common surrounding FLIBE or other suitable molten metal blanket. The primary magnetic guide field is generated by a superconducting magnet assembly surrounding the container in which the bundle of fusion sticks is mounted. A gas distributing valve mechanism is employed to independently and selectively supply gas and purge same in the respective fusion stick units, and an electrical switching mechanism is employed to similarly independently and selectively energize the fusion stick units in a desired timing pattern.

U. S. Patent No. 4,344, 911 to Maniscalco, et al. issued August 17, 1982 entitled "Fluidized wall for protecting fusion chamber walls"discloses an apparatus for protecting the inner wall of a fusion chamber from microexplosion debris, x-rays, neutrons, etc. produced by deuterium-tritium (DT) targets imploded within the fusion chamber. The apparatus utilizes a fluidized wall similar to a waterfall comprising liquid lithium or solid pellets of lithium-ceramic, the waterfall forming a blanket to prevent damage of the structural materials of the chamber.

U. S. Patent No. 4,347, 621 to Dow issued August 31,1982 entitled"Trochoidal nuclear fusion reactor"discloses a method and apparatus for the confining of a stream of fusible positive ions at values of density and high average kinetic energy, primarily of tightly looping motions, to produce nuclear fusion at a useful rate; more or less intimately mixed with the fusible ions will be lower-energy electrons at about equal density, introduced solely for the purpose of neutralizing the positive space charge of the ions. Ions under high kinetic energy are introduced into an annular reaction chamber having a primarily axial strong magnetic field and an essentially radial electric field and assume in the chamber a quasi-trochoidal motion in which the kinetic energies in their small diameter looping components of motion are greater by at least an order of magnitude, than the kinetic energies in the relatively slow crossed field advance motions with which the ions circulate circumferentially around the axis of the annular reaction chamber.

U. S. Patent No. 4,349, 506 to Rawls, et al. issued September 14, 1982 entitled "Thermomagnetic burn control for magnetic fusion reactor"discloses an apparatus for controlling the plasma energy production rate of a magnetic-confinement fusion reactor, by controlling the magnetic field ripple. The apparatus includes a group of shield sectors formed of fe, rromagnetic material which has a temperature-dependent saturation magnetization, with each shield lying between the plasma and a toroidal field coil. A mechanism for controlling the temperature of the magnetic shields, as by controlling the flow of cooling water therethrough, thereby controls the saturation magnetization of the shields and therefore the amount of ripple in the magnetic field that confines the plasma, to thereby control the amount of heat loss from the plasma. This heat loss in turn determines the plasma state and thus the rate of energy production.

U. S. Patent No. 4,354, 998 to Ohkawa issued October 19,1982 entitled"Method and apparatus for removing ions trapped in a thermal barrier region in a tandem mirror fusion reactor"discloses a method and apparatus for clearing thermal barrier regions of trapped ions in a tandem mirror fusion reactor apparatus utilizing a bend at each end of the cylindrical plasma chamber within which bend the thermal barrier is positioned. Ions trapped in the thermal barrier are caused by said bend to drift in a direction perpendicular to the incident magnetic field and the direction of centrifugal force, such that said ions are enabled to be collected in a divertor positioned along the ion drift path.

U. S. Patent No. 4,354, 999 to Priest issued October 19, 1982 entitled"Plasma confinement"discloses a fusion device wherein a laser beam is focused to the center of a spherical reaction chamber having a mirrored inner surface. The spherical reaction chamber is evacuated and surrounded by a concentric lithium jacket which is surrounded by a concentric cryogenic jacket in which is immersed a multi-axis loffe bar system. A mixture of deuterium and tritium plasma is continuously introduced into the reaction chamber at a metered rate through the preheat units and compressed at the center of the chamber by the electromagnetic field created by the superconductive loffe bar system. This mixture is ignited by the laser beam to create a steady-state, self-sustaining lithium blanket. Power is controlled by controlling the plasma input rate and energy is coupled out of the device by electromagnetic coupling or by recirculating the lithium through a heat exchanger.

U. S. Patent No. 4,363, 775 to Bussard, et al. issued December 14,1982 entitled "Controlled nuclear fusion apparatus"discloses a fusion power generating device having a relatively small and inexpensive core region which may be contained within an energy absorbing blanket region. The fusion power core region contains apparatus of the toroidal type for confining a high density plasma. The fusion power core is removable from the blanket region and may be disposed and/or recycled for subsequent use within the same blanket region. Thermonuclear ignition of the plasma is obtained by feeding neutral fusible gas into the plasma in a controlled manner such that charged particle heating produced by the fusion reaction is utilized to bootstrap the device to a region of high temperatures and high densities wherein charged particle heating is sufficient to overcome radiation and thermal conductivity losses. The high density plasma produces a large radiation and particle flux on the first wall of the plasma core region thereby necessitating replacement of the core from the blanket region from time to time. See also U. S. Patent No. 4,367, 193 to Bussard issued January 4,1983 entitled"Modular fusion apparatus using disposable core"and U. S.

Patent No. 5,049, 350 to Bussard, et al. issued September 17, 1991 entitled"Controlled thermonuclear fusion power apparatus and method".

U. S. Patent No. 4,370, 295 to Bussard issued January 25, 1983 entitled"Fusion- fission power generating device having fissile-fertile material within the region of the toroidal field coils generating means"discloses a fusion-fission reactor having a plasma containing toroidal fusion region for producing high energy neutrons from fusion reactions and a region external to the fusion region containing material which is both fissile with respect to high energy neutrons and fertile with respect to low energy neutrons. The device comprises a toroidal field generating means and a region of fissile-fertile material positioned within the region of the toroidal field generating means : The toroidal field generating means is positioned substantially adjacent the toroidal fusion region.

U. S. Patent No. 4,380, 855 to Deckman, et al. issued April 26,1983 entitled "Method for filling hollow shells with gas for use as laser fusion targets"discloses hollow shell laser fusion targets, such as glass microballoons, filled with gases of the type which do not permeate through the wall of the balloon. A hole is laser-drilled in the balloon, a plug is placed over the hole and gas is introduced into the balloon through the loosely plugged hole. Thereafter the plug is melted to form a seal over the hole, entrapping the gas within the target. The plug is, for example, a polymer such as crystalline polystyrene, or glass.

U. S. Patent No. 4, 381, 280 to Roberts issued April 26, 1983 entitled"Method and device for producing nuclear fusion"discloses a triggering device and method for producing nuclear fusion reactions and having two or more intense pulses of high energy electrons derived from a single source and delivered to a target along separate paths but arriving at substantially the same time. The electron beams are produced in the electrode space of an electron accelerator which utilizes a cathode for producing multiple electron beams. Each electron beam is injected into a separate conventional linear pinch discharge.

The high energy electron beams follow the pinch discharge and are delivered to the target.

The pinch discharge tubes are curved so that each electron beam approaches the target from a different direction for irradiating the target symmetrically. Return conductors strategically located on the outer surface of each pinch discharge tube maintains the curved discharge within the center of the tube and sustains the pinch.

U. S. Patent No. 4,397, 809 to Salisbury issued August 9,1983 entitled"Charged particle machine"discloses apparatus wherein atomic nuclei undergo fusion reactions by forming two beams of fusible ions traveling at fusion producing velocities opposed in rotation along spiral paths having common axes, common radii and occupy common space in a reaction zone for fusion producing collisions of ions in one beam with ions in the other beam. Sources produce the oppositely traveling circumferential beams. Radially directed electric fields are applied to the beams of strength increasing with increasing distance from the sources for beam compression into spiral paths of a common reduced diameter passing through common space in the zone to promote collisions between ions in the oppositely traveling beams as they travel in the common space. See also U. S. Patent No. 4,397, 810 issued Aug. 9,1983 entitled"Compressed beam directed particle nuclear energy generator".

U. S. Patent No. 4,401, 618 to Salisbury issued August 30,1983 entitled"Particle- induced thermonuclear fusion"discloses a nuclear fusion process for igniting a nuclear fusion pellet in a manner similar to that proposed for laser beams uses, an array of pulsed high energy combined particle beams focused to bombard the pellet for isentropically compressing it to a Fermi-degenerate state by thermal blow-off and balanced beam momentum transfer. Each combined particle beam is arranged to produce electric charge neutrality in a volume around the target so that space charge induced expansion is avoided.

Each high energy combined beam is produced by merging in neutralizing proportion a convergently focused stream of positive particles and at least one convergently focused stream of negative particles to form an electrically neutralized combined beam having a deBroglie wavelength focal pattern at the region of pellet collision. The momentum and fusible mass of the particle beams reduce the ablation loss and result in a larger fraction of the pellet being available for fusion reaction.

U. S. Patent No. 4,411, 755 to Herman, et al. issued October 25, 1983 entitled "Laser-assisted isotope separation of tritium"discloses methods for laser-assisted isotope separation of tritium, using infrared multiple photon dissociation of tritium-bearing products in the gas phase. One such process involves the steps of (1) catalytic exchange of a deuterium-bearing molecule XYD with tritiated water DTO from sources such as a heavy water fission reactor, to produce the tritium-bearing working molecules XYT and (2) photoselective dissociation of XYT to form a tritium-rich product. By an analogous procedure, tritium is separated from tritium-bearing materials that contain predominately hydrogen such as a light water coolant from fission or fusion reactors.

U. S. Patent No. 4,430, 291 to Chi issued February 7,1984 entitled"Packed fluidized bed blanket for fusion reactor"discloses a packed fluidized bed blanket for a fusion reactor providing for efficient radiation absorption for energy recovery, efficient neutron absorption for nuclear transformations, ease of blanket removal, processing and replacement, and on- line fueling/refueling. The blanket of the reactor contains a bed of stationary particles during reactor operation, cooled by a radial flow of coolant. During fueling/refueling, an axial flow is introduced into the bed in stages at various axial locations to fluidize the bed.

When desired, the fluidization flow can be used to remove particles from the blanket.

U. S. Patent No. 4,434, 130 to Salisbury to February 28,1984 entitled"Electron space charge channeling for focusing ion beams"discloses a fusion reaction system wherein a compressed spiral beam of electrons forms a cylindrical electron sheath and wherein oppositely directed cylindrical beams of fusible ions are projected through said electron sheath and are forced into a common thin cylindrical path located where the potential gradient in electron sheath is minimum.

U. S. Patent No. 4,440, 714 to Rose issued April 3,1984 entitled"Inertial confinement fusion method producing line source radiation fluence"discloses an inertial confinement fusion method in which target pellets are imploded in sequence by laser light beams or other energy beams at an implosion site which is variable between pellet implosions along a line. The effect of the variability in position of the implosion site along a line is to distribute the radiation fluence in surrounding reactor components as a line source of radiation would do, thereby permitting the utilization of cylindrical geometry in the design of the reactor and internal components.

U. S. Patent No. 4,446, 096 to Auchterlonie issued May 1, 1984 entitled"High speed plasma focus fusion reactor"discloses an electrical discharge thermonuclear reactor having a capacitor which is discharged into a reaction chamber through a low inductance distribution circuit funneling discharge current to a focus point in the reaction chamber so that the magnitude of the magnetic field intensity associated with the discharge current is generally inversely proportional to the square of the distance from the focus point. Then the circuit inductance is limited to a minimum value regardless of the absolute maximum distance from the capacitor to the focus point and thus the size of the capacitor. The distribution circuit has two outward-branching, interpenetrating three dimensional circuit networks of opposite polarity conveniently fabricated by stacking conductor plates having a generally cylindrical geometry. The distribution circuit spherically surrounds the reaction chamber so far as is practical so that the discharge rate, power and energy transfer to the reaction chamber are maximized.

U. S. Patent No. 4,454, 850 to Horvath issued June 19, 1984 entitled"Apparatus and method for energy conversion"discloses process and apparatus for liberation of energy by nuclear fusion involving isotopes of hydrogen gas. Highly ionized hydrogen gas containing a higher proportion of deuterium than in naturally occurring hydrogen is pressurized, together with an oxidizing gas within combustion chamber of reciprocating piston and cylinder engine. An electrical discharge within the combustion chamber causes generation of heat by atomic dissociation and exothermal recombination of hydrogen atoms and electrical excitation of ionized gas. Ionized deuterium in the hydrogen gas undergoes a nuclear fusion reaction with consequent liberation of heat energy and remaining hydrogen gas burns in the oxidizing gas to provide control on fusion reaction.

U. S. Patent No. 4,532, 101 to Doll issued July 30,1985 entitled"Articulated limiter blade for a tokamak fusion reactor"discloses a limiter blade for a large tokomak fusion reactor includes three articulated blade sections for enabling the limiter blade to be adjusted for plasmas of different sizes. Each blade section is formed of a rigid backing plate carrying graphite tiles coated with titanium carbide, and the limiter blade forms a generally elliptic contour in both the poloidal and toroidal directions to uniformly distribute the heat flow to the blade. The limiter blade includes a central blade section movable along the major radius of the vacuum vessel, and upper and lower pivotal. blade sections which may be pivoted by linear actuators having rollers held to the back surface of the pivotal blade sections.

U. S. Patent No. H24 to Kugel, et al. issued February 4,1986 entitled"Toroidal midplane neutral beam armor and plasma limiter"discloses for use in a tokamak fusion reactor having a midplane magnetic coil on the inner wall of an evacuated toriodal chamber within which a neutral beam heated, fusing plasma is magnetically confined, a neutral beam armor shield and plasma limiter is provided on the inner wall of the toroidal chamber to shield the midplane coil from neutral beam shine-thru and plasma deposition. The armor shield/plasma limiter forms a semicircular enclosure around the midplane coil with the outer surface of the armor shield/plasma limiter shaped to match, as closely as practical, the inner limiting magnetic flux surface of the toroidally confined, indented, bean-shaped plasma. The armor shield/plasma limiter includes a plurality of semicircular graphite plates each having a pair of coupled upper and lower sections with each plate positioned in intimate contact with an adjacent plate on each side thereof so as to form a closed, planar structure around the entire outer periphery of the circular midplane coil. The upper and lower plate sections are adapted for coupling to heat sensing thermocouples and to a circulating water conduit system for cooling the armor shield/plasma limiter. The inner center portion of each graphite plate is adapted to receive and enclose a section of a circular diagnostic magnetic flux loop so as to minimize the power from the plasma confinement chamber incident upon the flux loop.

U. S. Patent No. 4,568, 509 to Cvijanovich, et al. issued February 4,1986 entitled "Ion beam device"discloses a nuclear fusion device comprising a condensed phase fuel element and accelerated ion beams which ionize and compress the fuel element and initiate nuclear fusion reactions. In one of the embodiment beams comprising electrons in addition to ions are employed. A method is provided comprising synchronization, acceleration and focusing of the beams on the fuel target. A neutron generator is also provided.

U. S. Patent No. 4,569, 819 to David issued February 11, 1986 entitled"Pulsed nuclear power plant"discloses a spherical underground cavity filled with saturated steam or a mixture of saturated steam and coal dust in which a nuclear device is detonated to provide the source of energy. The energy thus released heats the saturated steam to produce superheated steam used to generate power. If coal dust is mixed with the saturated steam in the correct ratio, the rise in temperature caused by the nuclear explosion initiates a chemical reaction between the steam and the coal to produce carbon monoxide and hydrogen. The mixture of carbon monoxide and hydrogen can be used as fuel in an external power plant.

U. S. Patent No. 4,578, 236 to Gomei issued March 25,1986 entitled"Torus type nuclear fusion apparatus using deuterium or tritium as fuel"discloses a torus type nuclear fusion apparatus including a main limiter for contacting plasma generated in a space enclosed by a first wall of a blanket and maintaining the shape of plasma stable, and a sub- limiter arranged between the first wall and the outer circumference of plasma to neutralize helium ion, a product of fusion reaction.

U. S. Patent No. 4,608, 222 to Brueckner issued August 26,1986 entitled"Method of achieving the controlled release of thermonuclear energy"discloses a method of releasing thermonuclear energy by illuminating a minute, solid density, hollow shell of a mixture of material such as deuterium and tritium with a high intensity, uniformly converging laser wave to effect an extremely rapid build-up of energy in inwardly traveling shock waves to implode the shell creating thermonuclear conditions causing a reaction of deuterons and tritons and a resultant high energy thermonuclear burn. Utilizing the resulting energy as a thermal source and to breed tritium or plutonium. The invention also contemplates a laser source wherein the flux level is increased with time to reduce the initial shock heating of fuel and provide maximum compression after implosion.

U. S. Patent No. 4, 618, 470 to Salisbury issued October 21, 1986 entitled"Magnetic confinement nuclear energy generator"discloses a fusion reactor including a sphere. A first structure is disposed within the interior of the sphere for producing a magnetic field. A second structure is circumferentially disposed around the exterior of the sphere for producing a countermagnetic field. More structure is provided for injecting a gas containing fusible ions into the sphere. Yet more structure is also provided for heating the gas within the interior of the sphere, and for extracting heat from the sphere.

U. S. Patent No. 4,626, 400 to Jassby, et al. issued December 2,1986 entitled "Variable control of neutron albedo in toroidal fusion devices"discloses an arrangement for controlling neutron albedo in toroidal fusion devices having inboard and outboard vacuum vessel walls for containment of the neutrons of a fusion plasma. Neutron albedo material is disposed immediately adjacent the inboard wall, and is movable, preferably in vertical directions, so as to be brought into and out of neutron modifying communication with the fusion neutrons. Neutron albedo material preferably comprises a liquid form, but may also take pebble, stringer and curtain-like forms.

U. S. Patent No. 4,639, 348 to Jarnagin issued January 27,1987 entitled"Recyclotron III, a recirculating plasma fusion system"discloses apparatus designed to burn boron hydride. Boron hydride has no free neutrons on either side of its reaction equation. This fuel attempts to avoid issues associated with neutron-based fuels, deuterium-tritium (D-T) in particular. D-T gives off 80% of its energy in the form of neutrons. These make the apparatus radioactive; and the neutrons may be used to breed weapons grade fission material. The fuel of this invention cannot be used to make fission bomb material ; its product particles are ostensibly safe inert helium particles. B-H fuel is abundant, available and inexpensive. Boron hydride comes in gas, liquid or solid form, stable or unstable. The invention at hand proposes to accelerate macromolecular ions of boron hydride into one another, then reaccelerate the debris ions into one another also. This is to be done by recyclotrons--cyclotrons modified to recirculate a similar device's output. Recyclotrons take advantage of the fact that modest energies to a particle accelerator correspond to larger kinetic temperatures in a plasma.

U. S. Patent No. 4,642, 206 to Honig issued February 10,1987 entitled"Production of spin polarized fusion fuels"discloses methods for producing large, highly nuclear spin- polarized thermonuclear fuels HD, D2, HT and DT in a state where they can be stored and manipulated for appreciable times at ordinary liquid helium temperatures. Molecular mixtures, radiation treatments, symmetry species conversion catalysts, molecular species spatial arrangements, radio frequency irradiations and anneal programs are given to provide polarized D and polarized T in usable forms in the solid, liquid and high density gas phases.

U. S. Patent No. 4,650, 630 to Boyer issued March 17,1987 entitled"Process and apparatus for producing nuclear fusion energy"discloses an invention where two ion beams are accelerated on coincident paths in high vacuum with particle velocity vectors at 180 degrees relative to one another to increase collison and fusion probabilities. The ion beams may be of the same or of different polarities and may both be the same isotope, or may be respectively of deuterium and tritium. A heat exchange fluid such as liquid lithium is in heat exchange contact with the vacuum chamber to remove energy generated by fusion reactions between colliding and fusing particles of the two beams.

U. S. Patent No. 4,687, 618 to Nuckolls, et al. issued August 18,1987 entitled "Laser-fusion targets for reactors"discloses a laser target comprising a thermonuclear fuel capsule composed of a centrally located quantity of fuel surrounded by at least one or more layers or shells of material for forming an atmosphere around the capsule by a low energy laser prepulse. The fuel may be formed as a solid core or hollow shell, and, under certain applications, a pusher-layer or shell is located intermediate the fuel and the atmosphere forming material. The fuel is ignited by symmetrical implosion via energy produced by a laser, or other energy sources such as an electron beam machine or ion beam machine, whereby thermonuclear burn of the fuel capsule creates energy for applications such as generation of electricity via a laser fusion reactor.

U. S. Patent No. 4,696, 781 to Bourque issued September 29, 1987 entitled "Composite first wall for fusion device"discloses a first wall structure for use in a fusion device which surrounds the plasma region and includes a base wall which is substantially continuous. The base wall has an inner surface which faces the plasma region and an outer surface which faces the first wall coolant. The inner surface has a plurality of recesses. The wall structure also includes a number of inserts corresponding in number to the recesses with each insert being received in a respective recess and extending inwardly beyond the inner base wall surface. The inserts are made of material having a substantially greater heat flux capability than the material from which the base wall is formed.

U. S. Patent No. H446 to Kulsrud, et al. issued March 1, 1988 entitled"Method of controlling fusion reaction rates"discloses a method of controlling the reaction rates of the fuel atoms in a fusion reactor comprises the step of polarizing the nuclei of the fuel atoms in a particular direction relative to the plasma confining magnetic field. Fusion reaction rates can be increased or decreased, and the direction of emission of the reaction products can be controlled, depending on the choice of polarization direction.

U. S. Patent No. 4,729, 865 to Busch issued March 8,1988 entitled"Nuclear fusion reactor"discloses a nuclear fusion reactor serving to contain a totally organized tritium- deuterium plasma by guiding the self-bombarding particles in a resonating path of a particular wavelength and frequency, similar to a radio wave. Under these conditions the electrons ostensibly tend to remain cooler, which reduces plasma radiation energy losses.

Energy may be added to the plasma by axially distributed oscillators of the proper frequency, raising the plasma to ignition temperature and densities. Finally the ignited plasma directs its high energy neutrons into strategically located lithium blankets and the ionic energy levels are controlled by causing the plasma to generate an alternating electric current. Various types of alternate fusion reactions are briefly considered.

U. S. Patent No. 4,734, 246 to Ohkawa, et al. issued March 29, 1988 entitled "Elongated toroid fusion device"discloses a toroidal fusion device with an elongated axial cross section which is capable of ignition without auxiliary heating and with modest toroidal magnetic field. The device is based on the principle that for elongated toroids the toroidal current density in the plasma at ignition is subject to a limit which is proportional to the product of the elongation and the toroidal magnetic field. The elongation is made greater than about 4. The aspect ratio is preferably between about 3 and 10.

U. S. Patent No. 4,735, 762 to Lasche issued April 5,1988 entitled"Laser or charged-particle-beam fusion reactor with direct electric generation by magnetic flux compression"discloses a high-power-density laser or charged-particle-beam fusion reactor system that maximizes the directed kinetic energy imparted to a large mass of liquid lithium by a centrally located fusion target. A fusion target is embedded in a large mass of lithium, of sufficient radius to act as a tritium breeding blanket, and provided with ports for the access of beam energy to implode the target.

U. S. Patent No. 4,746, 484 to Jassby issued May 24,1988 entitled"Fusion reactor pumped laser"discloses a nuclear pumped laser capable of producing long pulses of very high power laser radiation is provided. A toroidal fusion reactor provides energetic neutrons which are slowed down by a moderator. The moderated neutrons are converted to energetic particles capable of pumping a lasing medium. The lasing medium is housed in an annular cell surrounding the reactor. The cell includes an annular reflecting mirror at the bottom and an annular output window at the top. A neutron reflector is disposed around the cell to reflect escaping neutrons back into the cell. The laser radiation from the annular window is focused onto a beam compactor which generates a single coherent output laser beam.

U. S. Patent No. 4,749, 540 to Bogart, et al. issued June 7,1988 entitled "Demountable tokamak fusion core"discloses a demountable tokamak fusion reactor core in which a demountable central portion contains at least the inner toroidal field producing legs of the tokamak toroidal field coil and the plasma containment vessel. Also in the demountable central portion may be poloidal field coils and a means of heating the plasma or heating and shaping the plasma, e. g. , an ohmic heating coil. The outer relatively permanent portion of the fusion reactor contains a blanket system within an opening formed by the current return legs of the toroidal field coil. Different embodiments of the ohmic heating coil could include a bucking cylinder toroidal magnet support.

U. S. Patent No. H508 to Mark issued August 2,1988 entitled"Hybrid-drive implosion system for ICF targets"discloses hybrid-drive implosion systems for ICF targets which permit a significant increase in target gain at fixed total driver energy. The ICF target is compressed in two phases, an initial compression phase and a final peak power phase, with each phase driven by a separate, optimized driver. The targets comprise a hollow spherical ablator disposed around fusion fuel. The ablator is first compressed to higher density by a laser system, or by an ion beam system, that in each case is optimized for this initial phase of compression of the target. Then, following compression of the ablator, energy is directly delivered into the compressed ablator by an ion beam driver system that is optimized for this second phase of operation of the target. The fusion fuel is driven, at high gain, to conditions wherein fusion reactions occur.

U. S. Patent No. 4,774, 065 to Penzhorn, et al. issued September 27,1988 entitled "Process and apparatus for decontaminating exhaust gas from a fusion reactor fuel cycle of exhaust gas components containing chemically bonded tritium and/or deuterium"discloses a process for decontaminating an exhaust gas from a fusion reactor fuel cycle of exhaust gas components containing at least one heavy hydrogen isotope selected from tritium and deuterium in compound form, the compound form being ammonia and hydrocarbon, the exhaust gas containing CO and hydrogen isotopes and in which the at least one heavy hydrogen isotope is liberated from its compound, separated out from the exhaust gas and fed back into the fuel cycle.

U. S. Patent No. H554 to Dawson, et al. issued December 6,1988 entitled"Toroidal reactor"discloses a method for producing fusion power wherein a neutral beam is injected into a toroidal bulk plasma to produce fusion reactions during the time permitted by the slowing down of the particles from the injected beam in the bulk plasma.

U. S. Patent No. H627 to Peng issued April 4,1989 entitled"Spherical torus fusion reactor"discloses a fusion reactor having a near spherical-shaped plasma with a modest central opening through which straight segments of toroidal field coils extend that carry electrical current for generating a toroidal magnet plasma confinement fields. By retaining only the indispensable components inboard of the plasma torus, principally the cooled toroidal field conductors and in some cases a vacuum containment vessel wall, the fusion reactor features an exceptionally small aspect ratio (typically about 1.5), a naturally elongated plasma cross section without extensive field shaping, requires low strength magnetic containment fields, small size and high beta. These features combine to produce a spherical torus plasma in a physics regime which permits compact fusion at low field.

U. S. Patent No. 4,853, 173 to Stenbacka issued August 1,1989 entitled"Method of producing fusion reactions and apparatus for a fusion reactor"discloses a method of producing fusion reactions comprising the steps of bringing deuterium ions from an ion source to run in a substantially closed path for accumulation of the ions to a predetermined density, whereupon the ions are deflected towards a reaction center inside this closed path.

An apparatus for a fusion reactor includes two annular, coaxially disposed magnets which are disposed to produce magnetic fields in a vacuum tank. The inner magnet produces a homogenous field transversely to the plane in which deuterium ions are intended to circulate prior to reaction, and the outer magnet produces an inhomogenous field which decreases outwardly in radial direction and is also directed transversely to the plane.

U. S. Patent No. 4,894, 199 to Rostoker issued January 16, 1990 entitled"Beam fusion device and method"discloses a fusion device for the reaction of atomic nuclei, preferably deuterons and tritons, to generate reaction products with kinetic energies convertible to useful energy. First and second sources of first and second positive ions provide such ions at temperatures in a range where the ions have a substantially optimum cross section for mutual reaction. The respective ions are accelerated to substantially the same mean velocity and formed into respective beams. The beams are neutralized and directed into a portion of a reaction chamber substantially orthogonally of a substantially constant unidirectional magnetic field as first and second polarized beams of respective first and second positive hot ions. The polarization of the first and second polarized beams is drained, preferably by a plasma created in the portion of the reaction chamber, to separate the neutralizing electrons from the respective first and second positive hot ions.

U. S. Patent No. 5,034, 952 to Mansfield, et al. issued July 23,1991 entitled"Laser for high frequency modulated interferometry"discloses a Stark-tuned laser operating in the 119 micron line of CH30H has an output power of several tens of milliwatts at 30 Watts of pump power while exhibiting a doublet splitting of about ten MHz with the application of a Stark field on the order of 500 volts/cm. This output power allows for use of the laser in a multi-channel interferometer, while its high operating frequency permits the interferometer to measure rapid electron density changes in a pellet injected or otherwise fueled plasma such as encountered in magnetic fusion devices. The laser includes a long far-infrared (FIR) pyrex resonator tube disposed within a cylindrical water jacket and incorporating charged electrodes for applying the Stark field to a gas confined therein. With the electrodes located within the resonator tube, the resonator tube walls are cooled by a flowing coolant without electrical breakdown in the coolant liquid during application of the Stark field. Wall cooling allows for substantially increased FIR output powers. Provision is made for introducing a buffer gas into the resonator tube for increasing laser output power and bandwidth.

U. S. Patent No. H984 to Brooks, et al. issued November 5,1991 entitled"Self- pumping impurity control"discloses apparatus for removing the helium ash from a fusion reactor having a D-T plasma comprises a helium trapping site within the reactor plasma confinement device, the trapping site being formed of a trapping material having negligible helium solubility and relatively high hydrogen solubility; and means for depositing the trapping material on said site at a rate sufficient to prevent saturation of helium trapping.

U. S. Patent No. 5,078, 950 to Bernadet, et al. issued January 7,1992 entitled "Neutron tube comprising a multi-cell ion source with magnetic confinement"discloses a sealed neutron tube which contains a low-pressure gaseous deuterium-tritium mixture wherefrom an ion source forms an ionized gas which is guided by a magnetic electron confinement field produced by magnets, which source emits the ion beams which traversed an extraction-acceleration electrode and which are projected onto a target so as to produce therein a fusion reaction which causes an emission of electrons.

U. S. Patent No. 5, 152,955 to Russell issued October 6,1992 entitled"Storage ring fusion energy generator"discloses intersecting storage rings, of the same type used in high energy nuclear physics research, for power generation. The device is optimized for lower- energy beam particles and higher beam current, adapted with a reaction chamber at the intersection of the rings to collect released fusion energy for conversion to electricity, and equipped with means to recapture scattered accelerated particles and reintegrate them into the focused beams for recirculation through the reaction chamber. The preferred beam particles, deuterium and tritium, are accelerated and injected into and focused by the storage rings, to collide nearly head on in the reaction chamber.

U. S. Patent No. 5,160, 694 to Steudtner issued November 3, 1992 entitled"Fusion reactor"discloses a fusion reactor based on the cusped geometry concept in which the problem of indefinite tight plasma containment with inherent stability and high compression of the contained plasma in the reaction zone is addressed by an electric potential pot surrounding the reaction zone and having an ion source at the upper potential pot edge.

U. S. Patent No. 5,160, 695 to Bussard issued November 3,1992 entitled"Method and apparatus for creating and controlling nuclear fusion reactions"discloses an apparatus and method of enhancing nuclear fusion reactions utilizing a plasma, made up of ions and electrons, contained within a region, and enhances the density of the plasma using a collision-diffusion compressional enhancement process. Ion acoustic waves generated within a central region of the system permit increased reflection and scattering of ions and thereby reduces their mean free path within the core region to permit increased ions density sufficient to enhance nuclear fusion reactions within the core.

U. S. Patent No. 5,162, 094 to Curtis issued November 10,1992 entitled"Fusion power generating system"discloses an approach utilizing light weight isotopes of hydrogen and helium. A potential well is created between two accelerating electrodes that, in a vacuum, allows ions from sources to be captured by the potential well. An axial magnetic field as created by solenoid causes the captured ions to pass through an ion focusing region and thus allowing fusion reactions to take place within the region. The magnetic field also confines the trajectory of the fusion products to a series of helixes preventing them from reaching the solenoid walls, but instead forces them to exit the two ends of the solenoid.

U. S. Patent No. 5,182, 075 to Gotoh, et al. issued January 26, 1993 entitled"Nuclear fusion reactor"discloses a nuclear fusion reactor having a vacuum vessel in which hydrogen isotope plasma is enclosed and a confining magnetic field generating coil for confining said plasma at a predetermined position in the vacuum vessel. It comprises a low tritium-permeable layer having lower tritium-permeability than that of a cooling metal base for forming a refrigerant passage for cooling the vacuum vessel on at least the surface adjacent to said plasma enclosed and a heat resistant and insulating fire member of the level higher than that of the cooling metal base for thermally shielding said low tritium- permeable layer from the plasma or corpuscular rays is formed on the low tritium- permeable layer.

U. S. Patent No. 5,198, 181 to Jacobson issued March 30,1993 entitled"Stabilizing plasma in thermonuclear fusion reactions using resonant low level electromagnetic fields" discloses particles including fusible nuclei and electrons that are contained in a fusion reaction vessel having a conductive length. The particles individually have a mass and a velocity, and are resonated by a weak magnetic field applied to the vessel at a magnetic flux density set according to a relation equating the gravitational energy of the particles with the electromagnetic energy of the applied magnetic field. The magnetic field can be applied in addition to stronger confinement and heating magnetic fields.

U. S. Patent No. 5,375, 149 to Fisch, et al. issued December 20,1994 entitled "Apparatus and method for extracting power from energetic ions produced in nuclear fusion"discloses an apparatus and method of extracting power from energetic ions produced by nuclear fusion in a toroidal plasma to enhance respectively the toroidal plasma current and fusion reactivity. By injecting waves of predetermined frequency and phase traveling substantially in a selected poloidal direction within the plasma, the energetic ions become diffused in energy and space such that the energetic ions lose energy and amplify the waves. The amplified waves are further adapted to travel substantially in a selected toroidal direction to increase preferentially the energy of electrons traveling in one toroidal direction which, in turn, enhances or generates a toroidal plasma current.

U. S. Patent No. 5, 410, 574 to Masumoto, et al. issued April 25,1995 entitled "Internal component of fusion reactor"discloses a fusion reactor having an internal component in which an internal structure assembly is housed in a toric vacuum vessel in an arrangement along a circumferential direction thereof and in which a high-temperature plasma in which hydrogen and hydrogen isotopes are maintained in a plasma state confined in a toric internal space defined in the internal structure assembly. The internal component includes a cooling structure of a multi-wall structure having multiple walls formed to the internal structure assembly and a flow channel formed in the cooling structure for a cooling fluid for extracting heat caused by plasma and a nuclear reaction.

U. S. Patent No. 5,572, 559 to Smith, et al. issued November 5, 1996 entitled "Radiography apparatus using gamma rays emitted by water activated by fusion neutrons" discloses radiography apparatus includes an arrangement for circulating pure water continuously between a location adjacent a source of energetic neutrons, such as a tritium target irradiated by a deuteron beam, and a remote location where radiographic analysis is conducted. Oxygen in the pure water is activated via the 160 (n, p) 16N reaction using 14- MeV neutrons produced at the neutron source via the 3H (d, n) 4He reaction. Essentially monoenergetic gamma rays at 6.129 (predominantly) and 7. 115 MeV are produced by the 7. 13-second 16N decay for use in radiographic analysis. The gamma rays have substantial penetrating power and are useful in determining the thickness of materials and elemental compositions, particularly for metals and high-atomic number materials.

U. S. Patent No. 5,818, 891 to Rayburn, et al. issued October 6,1998 entitled "Electrostatic containment fusion generator"discloses an electrostatic containment fusion generator comprising a generally spherical capacitor having an outer plate at ground and a negatively charged inner plate. A reaction chamber, comprised of two pairs of spaced apart permanent magnets, is disposed within the inner plate. An ion source means provides a deuteron beam to enter into a figure-8 orbit between the two pairs of magnets. A Faraday cage exists between the two pairs which neutralizes space charge in the center region of the beam. An arced cut portion on each magnet assists in the beam's entry into the Faraday cage, while a path correction means corrects the effects of the inverse field created by the cut portion.

U. S. Patent No. 5,825, 836 to Jarmusch issued October 20,1998 entitled "Tetrahedral colliding beam nuclear fusion"discloses a nuclear fusion reactor that operates by colliding particle beams from at least four different directions. The beams collide in a matrix that guides the particles to the reaction's center by their mutual electrostatic repulsion. In the preferred embodiment the reactor comprises primarily four high energy particle accelerators. At the reactor's center, the accelerators'four beams intersect at angles of approximately 109.47 degrees. Accelerated to fusion producing velocities, the four particle beams intersect in a high-vacuum reaction chamber. The resulting collision matrix funnels the accelerated particles into the center of the reaction zone causing some of the fuel particles to fuse rather than to scatter.

U. S. Patent No. 5,895, 533 to Kawamura, et al. issued April 20, 1999 entitled "Beryllium-copper bonding material"discloses a material for bonding pure beryllium to a copper alloy. The beryllium-copper material comprises a single layer or multiple layers having a thickness of 0.3-3. 0 mm and containing at least 50 atomic % of Cu is inserted between the pure beryllium and the copper alloy to prevent bonding strength from degrading in the bonding process or during operation of a nuclear fusion reactor, by effectively mitigating formation of brittle intermetallic compounds and generation of thermal stress at the bonding interface.

U. S. Patent No. 5,923, 716 to Meacham issued July 13, 1999 entitled"Plasma extrusion dynamo and methods related thereto"discloses a plasma extrusion dynamo and methods related thereto. Also featured are fusion reactors using such dynamos and methods.

In the methodology of the present invention, a steady-state stream of conductive plasma is forced by pressure or momentum to flow into a magnetic extrusion nozzle made up of converging magnetic field lines so as to form a closed, steady-state current loop within the plasma. The plasma current loop in turn forms a closed set of poloidal field lines that interact with the plasma current to compress and confine plasma in a toroidal volume.

U. S. Patent No. 5,949, 835 to Uhm, et al. issued September 7,1999 entitled"Steady- state, high dose neutron generation and concentration apparatus and method for deuterium atoms"discloses a steady-state source of neutrons produced within an electrically grounded and temperature controlled chamber confining tritium or deuterium plasma at a predetermined density to effect implantation of ions in the surface of a palladium target rod coated with diffusion barrier material and immersed in such plasma. The rod is enriched with a high concentration of deuterium atoms after a prolonged plasma ion implantation.

Collision of the deuterium atoms in the target by impinging ions of the plasma initiates fusion reactions causing emission of neutrons during negative voltage pulses applied to the rod through a high power modulator. The neutrons are so generated at a relatively high dose rate under optimized process conditions.

U. S. Patent No. 5,958, 105 to Ishitsuka, et al. issued September 28, 1999 entitled "Process for preparing metallic beryllium pebbles"discloses a method for stably producing metal beryllium pebbles each ranging from 0. 1 to 1. 8 mm in particle diameter and 0.05 to 0.6 mm in crystal grain average diameter. The metal beryllium pebbles obtained by the invention are excellent not only in tritium emission power but also in anti-swelling property, and are thus useful as a material for nuclear fusion reactors. The metal beryllium pebbles can also be advantageously employed for aerospace structural materials and the like, by utilizing their light weight and high melting point properties.

U. S. Patent No. 6, 411, 666 to Woolley issued June 25,2002 entitled"Method and apparatus to produce and maintain a thick, flowing, liquid lithium first wall for toroidal magnetic confinement DT fusion reactors"discloses a system for forming a thick flowing liquid metal, in this case lithium, layer on the inside wall of a toroid containing the plasma of a deuterium-tritium fusion reactor. The presence of the liquid metal layer or first wall serves to prevent neutron damage to the walls of the toroid. A poloidal current in the liquid metal layer is oriented so that it flows in the same direction as the current in a series of external magnets used to confine the plasma. This current alignment results in the liquid metal being forced against the wall of the toroid. After the liquid metal exits the toroid it is pumped to a heat extraction and power conversion device prior to reentering the toroid.

U. S. Patent No. 6,418, 177 to Stauffer, et al. issued July 9,2002 entitled"Fuel pellets for thermonuclear reactions"discloses fuel pellets for use as targets in a device employing thermonuclear fusion by inertial confinement (laser fusion). The pellets are manufactured from high polymer hydrocarbons in which bound hydrogen has been replaced with tritium. The required polymer is prepared by polymerizing monomer (s) which contain carbon and tritium. The hollow pellets are filled with thermonuclear fuel, e. g. , a mixture of deuterium-tritium. To improve the sphericity of the pellets and the uniformity of their wall thickness, manufacture of the pellets is contemplated in the near-zero gravity of space.

U. S. Patent No. 6, 611, 106 to Monkhorst, et al. issued August 26,2003 entitled "Controlled fusion in a field reversed configuration and direct energy conversion"discloses a system and apparatus for controlled fusion in a field reversed configuration (FRC) magnetic topology and conversion of fusion product energies directly to electric power.

Preferably, plasma ions are magnetically confined in the FRC while plasma electrons are electrostatically confined in a deep energy well, created by tuning an externally applied magnetic field. In this configuration, ions and electrons may have adequate density and temperature so that upon collisions they are fused together by the nuclear force, thus forming fusion products that emerge in the form of an annular beam. Energy is removed from the fusion product ions as they spiral past electrodes of an inverse cyclotron converter.

U. S. Patent No. 6,654, 433 to Boscoli issued November 25,2003 entitled"Method and machine for producing energy by nuclear fusion reactions"discloses an experimental machine for producing low-temperature nuclear fusion reactions, wherein an ion source feeds a flux of positive deuterium ions to a reaction chamber housing a target defined by active elements and by an aggregate of metal sulfate hydrated with heavy water; a pumping assembly being provided to maintain a vacuum in the reaction chamber; and the reaction chamber having an accelerating device for accelerating the positive deuterium ions, and which generates an electric field inside the reaction chamber to convey and accelerate the deuterium ions against the active element of the target in such a manner as to initiate nuclear fusion reactions between the incident deuterium ions and some of the atoms of the active element.

U. S. Patent Application Publication No. 20020080904 to Rostoker, et al. published June 27,2002 entitled"Magnetic and electrostatic confinement of plasma in a field reversed configuration"discloses a system and apparatus for containing plasma in which plasma ions are contained magnetically in stable, non-adiabatic orbits in a Field Reversed Configuration (FRC) magnetic topology. Further, the electrons are contained electrostatically in a deep energy well, created by tuning an externally applied magnetic field. The simultaneous electrostatic confinement of electrons and magnetic confinement of ions avoids anomalous transport and facilitates containment of both electrons and ions.

U. S. Patent Application Publication No. 20020101949 to Nordberg published August 1,2002 entitled"Nuclear fusion reactor incorporating spherical electromagnetic fields to contain and extract energy"discloses a nuclear fusion reactor system including a reactor core containing nuclear fusionable material and a plurality of conducting spheres arranged adjacent each other with at least two of said conducting spheres adjacent the reactor core. The reactor core and the conducting spheres form a electro/magnetic circuit such that fusion of fusionable material in the reactor core establishes an electro/magnetic flow around the electro/magnetic circuit.

U. S. Patent Application Publication No. 20020172316 to Matera, et al. published November 21,2002 entitled"Divertor filtering element for a tokamak nuclear fusion reactor; divertor employing the filtering element ; and tokamak nuclear fusion reactor employing the divertor"discloses a divertor for a TOKAMAK nuclear fusion reactor, having at least one target element for intercepting the path of contaminating particles from a toroidal channel in which plasma is formed and confined; and at least one grille structure interposed between a catch region, for catching the contaminating particles, and the input of a plasma purifying device.

U. S. Patent Application Publication No. 20030002610 to Panarella, published January 2,2003 entitled"Nuclear fusion and energy conversion apparatus"discloses a system and method for generating electrical energy utilizing nuclear fusion comprised of a containment device, a quantity of plasma with fusible substances in the containment device, the containment device and its contents being adapted for repeated cycle bursts of fusion reactions in response to high energy electronic pulses. The fusion containment device is mounted within a chamber containing a body of fluid such that thermal heat energy originating from the fusion reactions is gathered into the fluid body.

U. S. Patent Application Publication No. 20030031285 to Osipov, et al. published February 13,2003 entitled"Cryogenic layer of fusion fuel, fuel core and method for fuel core producing"discloses fuel for use with an inertial confinement fusion (ICF) reactor, and more specifically the target with condensed layers of the fuel and the method of its production. The invention enables formation of a transparent cryogenic layer from hydrogen isotopes, which retains its transparency when warmed up from 5K to 16-20K. To produce the above cryogenic layer inside micro spheres the method comprises rapid quenching of finely dispersed liquid state in the presence of the doping elements.

U. S. Patent Application Publication No. 20030223528 to Miley, et al. published December 4,2003 entitled"Electrostatic accelerated-recirculating-ion fusion neutron/proton source"discloses an electrostatic accelerated-recirculating-ion fusion neutron/proton source. The device acts as a compact accelerator-plasma-target fusion neutron/proton source which can emulate a line-type source. The unit comprises an axially elongated hollow vacuum chamber having an inner and outer wall. Reflectors are located at opposite ends of the vacuum chamber so that their centers lie on the axis of the vacuum chamber. A cathode that is transparent to oscillating particles is located within the vacuum chamber between the reflectors, defining a central volume and having the same axis as the vacuum chamber. Anodes that are transparent to oscillating particles are located near opposite ends of the vacuum chamber between the reflectors dishes and the cathode, having axes coincident with the axis of the vacuum chamber.

U. S. Patent Application Publication No. 20030230240 to Rostoker, et al. published December 18,2003 entitled"Magnetic and electrostatic confinement of plasma with tuning of electrostatic field"discloses a system and method for containing plasma and forming a Field Reversed Configuration (FRC) magnetic topology are described in which plasma ions are contained magnetically in stable, non-adiabatic orbits in the FRC. Further, the electrons are contained electrostatically in a deep energy well, created by tuning an externally applied magnetic field. The simultaneous electrostatic confinement of electrons and magnetic confinement of ions avoids anomalous transport and facilitates classical containment of both electrons and ions.

U. S. Patent Application Publication No. 20040017874 to Gray, et al. published January 29,2004 entitled"Modulated quantum neutron fusion"discloses the production of neutrons by the excitation of hydrogen atom valence electrons to the quantum state of a neutron, the synchronization of the quantity and rate of the production of those neutrons in order to synchronize their half-life decays for use in a fusion reaction, the use of phase alignment of the particle field oscillations to precipitate nuclear binding in a fusion reaction.

In addition to the substantially"hot"fusion techniques described above, so-called "cold"fusion techniques were briefly popularized, as ostensibly providing room- temperature fusion reactions. For example, U. S. Patent Application Publication No.

20030112916 to Keeney, et al. published June 19,2003 entitled"Cold nuclear fusion under non-equilibrium conditions"discloses a supposed method of producing cold nuclear fusion and a method of preparing a fusion-promoting material for producing cold nuclear fusion.

The method of producing fusion includes selecting a fusion-promoting material, hydriding the fusion-promoting material with a source of isotopic hydrogen, and establishing a non- equilibrium condition in the fusion-promoting material.

U. S. Patent Application Publication No. 20030215046 to Hornkohl published November 20,2003 entitled"Pressure generating structure"discloses a method and apparatus for forming a high pressure zone that can ostensibly initiate a fusion reaction. In accordance with the preferred embodiments, a superheated phase bubble is imploded in a reaction chamber to produce a high pressure region and initiate the fusion reaction. The reaction chamber has sloped edges that focus opposing shock waves created by the imploding phase bubble toward a high pressure reacting region. The liquid is filled with deuterium, tritium, uranium, unstable isotopes, and/or other materials that are susceptible to nuclear or chemical reactions at high pressures.

As of the present date, no such"cold fusion"techniques have been credibly shown to actually provide the stated benefits or any form of nuclear fusion.

Hence, despite the foregoing plethora of different approaches, there is still a tremendous unsatisfied need for practical and effective apparatus and methods for providing controlled nuclear fusion. Such apparatus and methods would provide not only an extremely abundant and clean source of energy for a variety of uses, but also could be adapted for other purposes including, inter alia, physics research and use as a weapon or deterrent.

Summary of the Invention The present invention satisfies the foregoing needs by providing, inter alia, improved apparatus and methods for providing controlled nuclear fusion.

In a first aspect of the invention, an improved fusion apparatus is disclosed. In one exemplary embodiment, the apparatus comprises at least one electromagnetic energy source (e. g., pulsed laser) adapted to introduce energy within one or more hollow glass fibers having Deuterium-based fuel disposed therein. Pondermotive forces and other phenomenon create sufficient conditions for fusion within the fiber (s), the effluent therefrom comprising a relativistic-velocity plasma stream.

In a second aspect of the invention, an improved electrical generation apparatus is disclosed. In one exemplary embodiment, the apparatus comprises a magneto-hydrodynamic (MHD) device adapted to utilize the aforementioned relativistic plasma in generating electrical potentials due to Lorentz forces.

In a third aspect of the invention, an improved method of generating energy is disclosed. The method generally comprises inducing fusion within a containment; ejecting a high-velocity stream of plasma ; and utilizing the plasma stream to generate electricity.

In a fourth aspect of the invention, an improved method of cascaded fusion is disclosed. The method generally comprises: providing a containment; disposing fusible fuel within the containment; inducing fusion within the fuel using a propagating wave source (e. g., laser) ; and inducing further (cascaded) fusion based at least in part on the propagation of the wave within the containment.

In a fifth aspect of the invention, an improved fusion core apparatus is disclosed. In one exemplary embodiment, the core comprises a micron-range block having a plurality of hollow channels disposed therein in a predetermined pattern. The channels may be tapered if desired. At least a portion of the channels are coated on their interior surfaces with palladium (deuterated), other deuterated metals, fusible compounds, or mixtures thereof, which acts as fuel for fusion when laser excitation energy is introduced into the channels.

In a sixth aspect of the invention, an improved fusion containment fiber is disclosed.

In one exemplary embodiment, the improved fiber comprises a glass-based longitudinal hollow fiber of the"holey"type. The fiber is coated on at least a portion of its interior with a palladium or similar coating, and is adapted to receive external fuel (such as adiabatically introduced deuterides).

In a seventh aspect of the invention, an improved fusion fuel configuration is disclosed. In the exemplary embodiment, the fuel comprises a deuterated metal such as palladium or lithium which is coated or impregnated on the interior surfaces of a fusion containment (e. g. , the aforementioned hollow core fibers).

In an eighth aspect of the invention, an improved method of introducing nuclear fuels such as hydrogen (e. g., Deuterium) or other fusible fuels into a containment is disclosed. In one exemplary embodiment, the method comprises providing porosity or holes within the walls of the containment, and disposing the fuel within the porous features or holes.

In a ninth aspect of the invention, an improved method of generating high-energy particles and/or electromagnetic energy is disclosed. The method generally comprises inducing fusion within a containment; ejecting a high-velocity stream of plasma (the plasma containing ions, subatomic particles, and electromagnetic energy); and utilizing the plasma stream or parts thereof for any number of purposes including e. g. , directed energy weapons.

In a tenth aspect of the invention, an apparatus for disposing nuclear fuel for use in a fusion reaction is disclosed. In one exemplary embodiment, the apparatus comprises one or more expendable fusion"cartridges"containing nuclear fuel which can be selectively inserted into a fusion apparatus, much as the cartridges in a conventional powder-based projectile weapon. The cartridges may also optionally be equipped with various nuclear spin isomers to enhance gamma ray or X-ray production (e. g. , wherein the nuclei are spin- aligned according to one or more desired orientations).

In an eleventh aspect of the invention, an improved collider apparatus is disclosed, wherein two or more relativistic plasma effluent beams are directed to collide with one another, thereby producing one or more desired species.

In a twelfth aspect of the invention, an improved gamma ray generating apparatus is disclosed. In one embodiment, "soft"X-rays are directed into a hollow core fiber or other chamber to interact with a specially configured fuel such as charged Hafnium. The interaction of the X-rays and fuel generates a high-intensity gamma burst out the effluent of the fiber.

Brief Description of the Drawings The features, objectives, and advantages of the invention will become more apparent from the detailed description set forth below when taken in conjunction with the drawings, wherein: Fig. 1 is a graphical representation of the prior art Ditmire, et al. experiment conducted at LLNL.

Fig. 2 is a graphical representation of the exemplary deuterium reaction generated using the apparatus of the present invention.

Fig. 3 is a perspective view of a first exemplary embodiment of a fusion core according to the present invention.

Fig. 3A is a side cross-sectional view of another exemplary embodiment of a fiber useful with the present invention, having an input focusing lens.

Fig. 3B is a side cross-sectional view of yet another exemplary embodiment of a fiber useful with the present invention, having a taper region at its input.

Fig. 4 is a perspective view of an alternative embodiment of the fusion core of the present invention.

Fig. 5 is a cross-sectional view of another alternative embodiment of the fusion core of the present invention, showing a tapering fiber containing a fuel.

Fig. 6 is a cross-sectional view of yet another alternative embodiment of the fusion core of the present invention, showing a central tapering fiber and adjacent fibers with each fiber receiving a laser pulse having a different wavelength.

Fig. 7 is a partial cutaway view of another alternative embodiment of the fusion core of the present invention comprising a single lumen fiber containing a fusion fuel.

Fig. 8 is a side plan view of yet another alternative embodiment of the fusion core of the present invention showing a curved configuration of an optical fiber.

Fig. 9 is an end perspective view of another alternative embodiment of the fusion core of the present invention showing a fiber having a central larger-diameter lumen surrounded by an array of smaller-diameter fiber lumens.

Fig. 10 is an end perspective view of an alternative embodiment of the fiber shown in Fig. 9, wherein the core comprises multiple fibers configured into an array and having intermediate material between the lumens through which optical energy may couple into adjacent optical fibers.

Fig. I I is an end perspective view of an alternative ("holey fiber") embodiment of the fusion core of the present invention showing a single-lumen fiber having multiple fiber layers each having a different index of refraction from adjacent layers.

Fig. 12 is top plan view of an exemplary fusion core of the present invention showing a circular fiber configuration for recirculation of laser energy and plasma.

Fig. 13 is a top plan view of yet another alternative embodiment of the fusion core of the present invention showing a circular fiber configuration formed with multiple fuel- introduction and laser energy ports.

Fig. 13A is perspective view of yet another alternative embodiment of the fusion core of the present invention showing a helical fiber configuration formed with multiple fuel-introduction ports.

Fig. 13B is perspective view of yet another alternative embodiment of the fusion core of the present invention showing multiple concentric helical fibers.

Fig. 13C is perspective view of yet another alternative embodiment of the fusion core of the present invention showing multiple interlaid helical fibers.

Fig. 13D is plan view of yet another alternative embodiment of a collider apparatus of the present invention showing two substantially coplanar fiber rings.

Fig. 13E is perspective view of yet another alternative embodiment of the collider apparatus showing a three-dimensional configuration of multiple fiber rings.

Fig. 14 is a cross-sectional view of an exemplary embodiment of a self-contained fuel element for use with the fusion apparatus of the present invention.

Fig. 15 is a cross-sectional view of an alternative embodiment of the fusion core of the present invention showing a fiber formed with a number of input fibers.

Figs. 16 A-D are end perspective views of various alternative embodiments of the fibers useful in the fusion core of the present invention.

Fig. 17 is a diagrammatic representation of an alternative embodiment of the fusion core of the present invention showing a fusion core at least partially surrounded by a heat transfer system.

Fig. 18 is a perspective view of an exemplary MHD generator system adapted for using the plasma ion effluent from the fusion core (s) previously referenced.

Detailed Description of the Invention Reference is now made to the drawings wherein like numerals refer to like parts throughout.

It will be recognized by those of ordinary skill that the embodiments described herein are merely exemplary of the broader concept of providing practical nuclear fusion.

Many different variations of physical configuration (some of which are described herein) may be employed consistent with the invention.

It will be further recognized that while the exemplary embodiments are described in terms of fusion fuel sources of hydrogen and various isotopes thereof, the present invention may feasibly be practiced using other species, including many elements and their isotopes which have an atomic weight heavier than hydrogen. For example, lithium, helium, carbon, nitrogen, oxygen, argon, and even iron may be used as the"fuel"for the present invention when properly adapted, whether in elemental or chemical compound form. Similarly, ordinary"light"water can even be used within certain embodiment to provide the necessary fuel.

It will also be appreciated that while described in the context of a magneto- hydrodynamic (MHD) generator, the plasma and particulate/EM output of the exemplary fusion apparatus may be used in a variety of different uses, only one of which is producing electrical energy. For example, the relativistic plasma beam may be used for heating or cutting of materials, ion bombardment of materials, generation of X-rays, gamma rays, or neutrons, for material fabrication, or even conceivably spacecraft propulsion. Myriad different uses for the practical plasma/energy source disclosed herein are possible.

Furthermore, as described subsequently herein, the use of an MHD device is merely illustrative of the broader principles of making use of the device effluent.

As used herein, the term"fiber"is meant to include any substantially longitudinal containment structure, including, for example, extruded or drawn glass-based fibers. While certain embodiments of the invention are described in terms of so-called"holey"fibers having a taper or tapered region, it will be appreciated that other types and configurations of fibers may be used consistent with the invention, the foregoing being merely exemplary.

For example, one alternate embodiment of the invention utilizes quartz fibers or chambers having no taper. Myriad other configurations and materials are possible.

As used herein, the term"laser"is intended broadly to mean any source of at least partly coherent electromagnetic energy including without limitation optical light devices, X- ray devices, UV-devices, I. R devices, and magnetic devices (e. g., MASERs).

As used herein, the term"effluent"refers simply to any energy, matter, or other product of the fusion reaction (or byproducts of associated reactions or physical phenomena).

Overview- In one aspect, the present invention discloses a fiber-based technology for producing, containing, and controlling light element (deuterium, for example) nuclear fusion reactions, and generating direct electrical power or other useful byproducts from the same reactions. In the exemplary embodiment, the approach uses lasers (e. g. , femto-second lasers) to produce high-energy fusion plasma, and a hollow glass fiber technology for confining the fast moving plasma, fueling the nuclear reactions, and generating useful output (e. g., electrical power).

In the exemplary embodiment, multiple glass fibers (or other light conducting fibers including, for example, layered polymer fibers, photonic crystal fibers or PCF, etc. ) with hollow cores are bundled and fused together to form a"fusion core". This core has the appearance and light conducting functionality of what is commonly called"crystal"or "holey"fibers. The exemplary fusion core can be small enough to fit onto a tabletop, and contains an integral electrical power generator, to convert fusion plasma energy directly into electrical energy. The electrical generator can be as simple as a coil of electrical conducting wire wrapped around the core as in the winding of an electrical transformer, if desired. The fusion core can be linear in shape, curved, a circle, or even other shapes, such as 3- dimensional helix for example. A circular design allows recirculation of both laser pulses and plasma for a cascade fusion reaction.

The exemplary core has ports, which allow laser light, fusible material, and plasma products to enter or exit. These ports can be, for example, other hollow fibers that are spliced onto the fusion core at its ends, or tangentially at multiple locations in the case of curved or circular shaped fusion cores. Additionally, the fusion core can made of porous glass, be made porous at elevated temperatures, or have transverse holes to allow more fuel to continuously enter from the sides, and be flow-controlled.

Innovative features of the hollow fibers of the exemplary embodiment are that they can contain a solid fusible material, such as deuterated Lithium (D-Li) or deuterated Palladium (D-Pd), deposited on the inner walls of the fibers; and porosity (or holes) in the fiber walls to allow external based fuels (such as deuterium gas, light and heavy water, and heavier elements) to enter the hollow core in gas, liquid, or solid forms. Laser beams produce field ionization and fusion reactions in the hollow fibers, and by the laser's presence in adjacent fibers, contribute coupled, pondermotive forces to further accelerate the charged plasma particles down the fibers for additional reactions. As conductors of light energy, the hollow fibers also capture photons radiated by accelerated plasma charges contained within the hollow fibers (e. g., Bremsstrahlung or"breaking"radiation), and confine them to the hollow core where they can add to the existing laser pulses, and further accelerate the charged plasma particles in the fiber core. In the well-known tokamak configuration (as well as others), the radiated photons from circulating/accelerating charges are lost, greatly reducing the power efficiency of the design.

The femto-second lasers initially produce plasma necessary for fusion by the "Wakefield effect", from the fusible fuel placed into the fibers. The plasma travels in the direction of the laser beam, while the laser fields inside the fibers accelerate the charged plasma particles to energies on the order of 100 MeV and higher with their pondermotive (Lorentz) forces. The plasma strikes additional fusible material inside the fibers (for example, Deuterium), and fuel introduced by fiber wall holes or porosity, producing more fusion energy. Energetic alpha particles and electrons from these reactions, and remnants of the laser pulse, continue down the fiber and in a"cascade reaction", heat more fusible fuel and induce more nuclear reactions. The hollow fibers can even be nested and drawn down in a taper if desired, to a"convergence zone"of sub-micron size. The inner tubes contain the plasma, while the outer tubes continuously conduct fresh fusion fuel gas mixtures and laser beams to the convergence zone, where additional fusion takes place.

Additionally, neutrons generated from the fusion reaction can strike introduced Lithium-6 material (e. g., Lithium Deuteride) and breed other species (including Tritium) which, with the Deuterium, can produce additional fusion reactions inside the fibers.

The glass fiber tubes that make up the exemplary fusion core have multiple functions, including (i) acting as light waveguides for the femto-second radiation and confinement; (ii) containing the confined fusion plasma ; (iii) containing the solid D-Pd, D- Li, or other fusible fuel ; (iv) allowing additional fuel to enter the core through porosity and holes in the fiber walls ; and (v) containing an integral MHD (Magneto Hydrodynamic) electrical generator.

Salient aspects of the exemplary embodiment (s) include the use of hollow glass fibers to contain plasmas, laser beams, and deuterium fuels; simultaneous use of both inertial and laser fusion containment methods; use of tapered fibers to intensify laser radiation; use of fiber mode coupling to intensify laser radiation; use of porous glass fiber or glass fibers with holes in the walls, to introduce fusion fuel (such as Deuterium) into the hollow fiber core; use of an integral MHD generator on the fibers, for close proximity to the charged fusion reaction products (the plasma) ; and use of fusion fuels that include light and heavy water introduced into the fiber cores via fiber porosity and holes in the walls of the tubes. These and other aspects of the invention are now described in detail.

Many of the exemplary embodiments of the present invention are examples of "micro fusion"versus the"macro fusion"approach characteristic of present day technologies in inertial and fast igniter fusion (where large and numerous lasers are used within stadium-sized machines). Herein lies one of the most salient distinctions and improvements over the prior art; i. e. , use of containment chambers (e. g., glass fiber configurations) measured in inches or even millimeters rather than hundreds of meters.

Costs associated with the exemplary apparatus and methods described herein are at least 3 to 4 orders of magnitude smaller than with their larger predecessors, owing at least in part simply to reduced size and complexity. Similarly, the smaller and simpler components are easier to manufacture, maintain and repair. Working on such a small spatial scale compared to the larger scale configurations at Lawrence Livermore National Laboratory (LLNL) or others further allows the present invention to be disposed on platforms or used in applications previously impossible with the prior art. For example, a fusion power supply such as that described herein can be rendered for use on a land vehicle (e. g. , automobile, battle tank, truck, train, etc. ), ship, aircraft, spacecraft, and any other number of uses. It is further envisaged that the various aspects of the invention can be further compacted spatially, and even reduced to a much smaller size so as to be effectively"hand held".

Applications would then include personal electronics, "fusion electric batteries or FEB"for electric cars, boats and planes. Such FEB can also be used to power weapons, radar, and communications.

In a weapons capacity, the particle and/or electromagnetic energy"beam"emitted from the discharge of the exemplary device described herein may also feasibly be used as a portable weapon, with reductions in femto-second or other laser/source size as technology advances permitting the weapon to even become hand-held.

Description of Exemplary Embodiments Various aspects and embodiments of the present invention are now described in detail.

However, it is first useful to discuss various aspects of nuclear fusion in general in order to provide additional context for the improvements of the present invention.

Fusion reactors must provide a high enough temperature to enable the fuel particles to overcome the repulsive Coulomb barrier (between protons or deuterons), and to maintain this temperature long enough and with sufficient ion density to get a net yield of energy. A net yield of energy means more energy out than was put into the plasma to heat it.

This net energy out condition is usually stated in terms of the product of ion density (n) and confinement time (T), and is known as Lawson's criterion : nr 2 10'4 s/cm3 for deuterium-tritium fusion nr 1016SICM3 for deuterium-deuterium fusion Eqn (1) Confinement time is defined as the time the fusion plasma is maintained at a temperature above the critical ignition temperature. This critical temperature is typically greater than 100 million degrees Kelvin. A close approach to Lawson's criterion has been at the TFTR at Princeton. Ignition temperature was reached, but the ion density was too low for practical benefit.

Since the confinement times associated with the use of femto-second lasers are 10-13 to 10-'4 seconds, the challenge for controlled laser fusion, with a net positive energy balance, is to increase the ion density and confinement times to meet the Lawson criterion.

More fusion fuel than that of small pellets (such as those used by the Lawrence Livermore apparatus) is needed, as well as a longer laser confinement time.

In the exemplary embodiment, the present invention overcomes these disabilities by use of solid (e. g. , deuterium containing) fuel material inside the glass, fiber tubes. By having this fuel material extend many millimeters along the inside of the tube (and optionally introducing fuel via the tube wall), the present invention advantageously increases the laser confinement and interaction time, as well as the ion density.

When light nuclei such as hydrogen and deuterium are forced together by a pulsed femto-second laser beam, they can fuse with a positive yield of energy. The mass of the combination (resultant) nucleus is less than the sum of the masses of the individual nuclei.

According to the generalized Einstein mass-energy relationship (E = mc2), the decrease in mass appears in the form of useful energy.

One of the optimized hydrogen fusion reactions used in the exemplary embodiment comprises the fusion of two heavy isotopes of hydrogen, deuterium (2H) and tritium (3H).

This reaction is the most energetic, yielding 17.6 MeV energy. The equation for the reaction is : 12H+13H#24He+01n+17.59 MeV Eqn (2) Byproducts of this reaction are energetic neutrons and helium ions (alpha particles). The reaction requires a relatively low temperature of 40 million degrees K to overcome the coulomb barrier between the deuterium and tritium ions. The deuterium fuel is abundant (ocean water has 1 part in 5000 of the hydrogen as deuterium), and the tritium (a radioactive isotope with a half-life of about 12 years) is"bred"from Lithium-6 by slow neutron bombardment in the reaction: 36Li+01 o 4He+3, H (tritium) +4. 8 MeV Eqn (3) As an option, faster neutrons can also bombard Lithium-7 producing tritium.

If a gallon of seawater is viewed as a potential fuel for a hydrogen fusion reactor, the deuterium in it could produce as much fusion energy as approximately 300 gallons of gasoline.

Other hydrogen fusion reactions include two key"D-D"reactions (used by Ditmire's Deuterium cluster experiment at LLNL): 12H+12H#23He+01n+3.27 MeV 2H+2H o3H (tritium) +'H (proton) +4. 03 MeV Eqn (4) In the first reaction, the helium-3 product can further react with the deuterium to produce helium-4 plus a proton and 18. 3 MeV of energy by the reaction: 12H+23He#24He+11 H +18. 3 MeV Eqn (5) Aside from the neutron, the hydrogen fusion products are all energetic, charged particles that can be used in an MHD electric power generator (described subsequently herein) in close proximity to the reactions. Additionally, the neutrons produced can further react with Lithium-6 in the fibers to produce Tritium fuel.

All the fusion reactions which can occur with deuterium can be considered to form a deuterium cycle, and combined into one"super"reaction yielding 43.2 MeV of energy. The combined equation for this reaction is: 6 ; H 2ZHe+2 ; H+2on+43. 2MeV Eqn (6) The charged by-products are electrons, alpha particles (helium nuclei) and protons, which can all be used in the MHD generator to produce electrical power. The neutrons can also be used to produce more charged particles, by their reactions with, inter alia, Lithium.

The best and most recent results demonstrating laser fusion of deuterium are those produced by Ditmire and associates at the Lawrence Livermore National Laboratory, starting in 1999. Ditmire observed the production of fusion neutrons from exploding, frozen, deuterium clusters, using a low energy, high repetition rate (10 Hz) table-top laser.

It produced 100 mJ, 35 fs laser pulses; see, e. g. ,, et al, Nature 398,492 (1999) (hereinafter "Ditmire"), and J. Zweiback and T. Ditmire, "Femtosecond laser energy deposition in strongly absorbing cluster gases diagnosed by blast wave trajectory analysis", p. 4545, Physicas of Plasmas, American Institute of Physics, 23 February 2001 ("Zweiback"), both incorporated herein by reference in their entirety. Ditmire obtained a yield of about one hundred thousand 2-3 Mev neutrons per laser pulse. Fig. 1 shows the experimental setup of Ditmire. This approach does not have the ability to reach the fusion"ignition"conditions of the larger NIF (National Ignition Facility) laser now under construction at Lawrence Livermore for reasons related to the Lawson Criterion. Specifically, ion density is too low, confinement times too short, and the laser beam diverges too quickly after the interaction with the clusters, to transfer all its energy to the resulting plasma.

Similar approaches to Ditmire are also being undertaken in England, France, Japan, Italy, and Russia, among others. Laser-cluster interaction studies are underway at the Saclay laboratory in France, by M. Schmidt. More recent experiments done in the UK by R.

Kodama, use cluster fuels of deuterium and tritium, as well as timed double-pulse lasers.

All the investigators generate deuterium cluster fuel for the D-D fusion reaction, by expanding high pressure deuterium gas into a low-pressure"vacuum". Under these adiabatic conditions, the temperature of the deuterium drops abruptly, and frozen clusters of the gas containing 1 to 10 thousand atoms are formed. The gas expansion nozzle and back pressure of the vacuum regulate the cluster sizes. The separations of the frozen clusters in this"spritz"of fuel are quite large and dramatically lower the total efficiency of the process.

The deuterium clusters form a bridge between single atoms, molecules, and bulk material, and limit the resulting plasma ion density. In addition, in the Ditmire experiments, the plasma confinement time is limited to the laser transit time through 1-3 millimeters of frozen deuterium gas. Each cluster is only a few millionths of a millimeter in size, but is illuminated in a focused laser beam about 1 micron in size, with an intensity of 102° watts per cm2. The inefficiency of this process to ignite many reactions is readily apparent to those of ordinary skill.

Each deuterium cluster becomes in effect a superheated, exploding ball of plasma when struck by a femto-second laser pulse. The ball of plasma expels high-energy charged particles capable of inducing D-D fusion in nearby clusters. Neutron time-of-flight measurements from the clusters to detectors confirm that their measured 2.45 Mev energies are consistent with D-D fusion.

When high intensity laser light passes through the clusters, field ionization is produced, dislodging electrons from the constituent atoms, in the direction of the laser pulse. Although this process is complicated, the laser direction taken by the electrons is dictated substantially by conservation of linear momentum and energy. The initially "stationary"electrons acquire kinetic energy from the incoming photons, in the direction of the laser pulse. The same process on a much lower energy scale is described by the well known Compton scattering phenomenon.

As the electrons move away at"relativistic"speeds (i. e. , approximately the speed of light), the atoms become charged deuteron ions, and a large electron current is produced.

The electric and magnetic fields of this current contribute to an enormous force on the charged deuterons. The force pulls and accelerates them in the direction the electrons are moving. The electrons acquire energies typically in excess of 100 MeV, and the deuteron ions acquire energies in excess of 15 MeV, all within distances measured in microns. These energies are sufficient to produce fusion.

The high-energy deuteron ions collide and fuse with deuterons from adjacent clusters, producing neutrons, electrons and helium ions of high energy. Fig. 2 illustrates this reaction, showing deuterium ions coming together and fusing to form a helium-3 ion plus a neutron. In the literature, this process is known as"fast ignition fusion" (FIF) because no external electric or magnetic fields are used for confinement.

Several exemplary embodiments of the invention described herein produce laser- induced fusion reactions inside hollow containments (e. g., glass fibers, bored block, etc. ).

These fibers are made out of fused silica, but may be fabricated out of other materials as well, including without limitation composites, ceramics, polymers, and even porous glass, or glass with sub-micron holes. Lead glass can be used alone or in combination for its ability to stop gamma and X-rays, while"doped"glass may be used as a laser amplifier, to further increase laser field strength and enhance fusion reactions, and also reflect neutrons if desired. Notably, quartz fibers have very low (approaching zero) coefficient of expansion, and hence will not yield to the significant thermal stresses present under rapid heating and/or cooling. Other materials may be used to supplement or replace the hollow fused silica fibers described herein as well, even including for example a"plasma channel"such as that utilized within a conventional prior art Tokamak. As is well known, plasma channels cannot only contain laser beams, but also can cause them to"self-focus"into smaller diameter directed beams with higher power densities. Hence, the present invention can utilize literally any"containment"vessel or structure which can contain the high-energy laser pulses and associated pondermotive forces sufficiently. Different configurations and materials adapted to for enhancing the desired properties will be readily apparent to those of ordinary skill in the laser arts provided the present disclosure.

In alternative configurations of the invention, microtubules (or even so-called "nanostructures") of carbon may also find use as neutron moderators, fuel matrices, and containment vessels, with their unusual properties. Besides graphite and diamond, carbon exists as C-60 in structures primarily composed of hexagons and heptagons whose edges are formed by the carbon-carbon bonds. The first and best known of these structures is the Buckminster-Fullerene C-60"bucky-ball". The bucky-ball is composed of 20 hexagons and 12 heptagons arranged in the same way as the'facets'on a soccer ball (i. e. , truncated icosahedron).

Each carbon atom in an all-carbon C-60 fullerene network is bonded to three other carbon atoms. The C-60 fullerene network forms a molecule with a cage-like structure and generally aromatic properties. All-carbon fullerene networks contain even numbers of carbon atoms generally ranging from 20 to 500 or more. Larger fullerenes are known as well, with many hundreds of carbon atoms bonded together in a fullerene network.

Additionally,"nested"fullerenes (hyperfullerenes) may be prepared wherein one closed fullerene structure is contained within a second larger closed fullerene structure, these structures being contained in turn within a larger closed fullerene structure. While these hyperfullerene spheroidal carbon molecules are considered to be the most stable forms of fullerenes in terms of cohesive energy per carbon atom, other shapes are possible.

Another useful aspect of the carbon fullerene (e. g. , C-60) is the ability to dispose one or more entities such as a fuel structure of impregnated palladium deuteride or other such fuel within the"cage"of the molecule. The truncated icosahedron structure produces a cavity or void within the fullerene, which, depending on the fullerene configuration, may act to contain or house and protect molecules contained therein. Such contained molecule may be captured within the fullerene until one or more carbon-carbon bonds are broken (such as the carbon atom cage being obliterated under the energy of the laser pulses within the fiber lumen), thereby opening a"window"for the extraction or escape of the molecule.

Numerous mechanisms for breaking carbon-carbon bonds within a fullerene are known to those of ordinary skill, and accordingly will not be described in detail herein.

The production of C-60 or other fullerene structures containing"captured" molecules or atoms (including radioactive species) is also well known. See for example, U. S. Patent No. 5,350, 569 entitled"Storage of Nuclear Materials by Encapsulation in Fullerenes"issued September 27,1994, and U. S. Patent No. 5,640, 705 entitled"Method of Containing Radiation Using Fullerene Molecules"5, 640,705 issued June 17, 1997 ; U. S.

Patent No. 6, 171, 451 entitled"Method and apparatus for producing complex carbon molecules"issued January 9,2001 ; U. S. Pat. Nos. 5, 510, 098,5, 316,636, 5,494, 558 and 5,395, 496, which use various processes to vaporize carbon rods, producing carbon atoms that recombine into fullerenes ; U. S. Patent No. 5,951, 832,"Ultrafine particle enclosing fullerene and production method thereof'issued September 14,1999, wherein atomic or crystalline species are driven into nanostructure structures using an energetic electron beam; and U. S. Patent No. 5,965, 267 entitled"Method for producing encapsulated nanoparticles and carbon nanotubes using catalytic disproportionation of carbon monoxide and the nanoencapsulates and nanotubes formed thereby"issued October 12,1999, which are each incorporated by reference herein in their entirety.

Furthermore, the shape of all C-60 structures is not necessarily spherical. Football and cigar shaped structures have been reported, and very long capped tubes ("bucky tubes", or carbon nanotubes) have been produced. Nanotubes generally comprise a network of hexagonal graphite rolled up onto itself to form a hollow tube-like structure. These nanotubes have been made with diameters as small as roughly one (1) nanometer. The length-to-width aspect ratio of nanotubes can be made extremely high, with lengths on the order of a millimeter or more (I E06 nm) compared to diameters on the order of a few nm.

Single-walled carbon nanotubes (SWNTs) are produced by any one of several methods, including (i) carbon arcing to vaporize a metal-impregnated carbon electrode ; (ii) laser ablation of a heated target; and (iii) catalytic chemical vapor deposition (CCVD), the latter comprising a low temperature technique more suited for large scale production of nanotubes. See, e. g. , U. S. Patent No. 5, 916, 642 entitled"Method of encapsulating a material in a carbon nanotube"issued June 29,1999, incorporated herein by reference in its entirety.

Another deposition technique for either individual or multiple multi-walled carbon nanotubes is based on electron beam lithography. Carbon nanotubes are deposited from the solution phase onto a substrate through lithographically determined openings in an electron beam photoresist layer. The openings may be in size from a few microns upwards. See Yang, Xiaoyu,"Carbon nanotubes. Synthesis, Applications, and some new aspects", Thin Films and Nanosynthesis Laboratory, Department of Mechanical and Aerospace Engineering, SUNY at Buffalo, Fall 1999, incorporated herein by reference in its entirety.

It has further been found that selective dissolution of portions of the nanotube (i. e., the so-called"end caps") may be accomplished through exposure of the nantoubes to certain oxidizing substances such as acids. See, for example, U. S. Patent No. 6,090, 363, entitled"Method of opening and filling carbon nanotubes"issued July 18,2000, incorporated herein by reference. Selective dissolution techniques may be used to prepare nanotubes for filling after formation of the tubes.

The foregoing hollow fibers advantageously substantially contain the laser beams, the solid deuterium or other fuel, the photon"force fields", the charged reaction-particles, gaseous fuels used for, e. g. , the generation of electrical power, as will be described in greater detail subsequently herein.

The hollow glass fibers referenced above are in the exemplary embodiment arranged in a geometric pattern, with the correct dimensions to allow laser radiation to enter and propagate, and to provide a support for solid, deuterium-containing fuel, coated on the inside walls of the fibers or otherwise introduced into the fiber lumen. This collection of fibers of small (e. g. , micron) size are initially prepared from a geometrically similar bundle of millimeter size fibers called a"preform". As is well known in the fiber forming arts, the preform is heated in a furnace, to soften the glass, and pulled or"drawn down"to the micron sizes. The fibers are reduced in size and fused together to form the glass"fusion core". By applying air pressure to the preform, the hollow openings or lumens remain at the end of the process. The pulled down core is a miniature in all respects of the larger preform.

It will be recognized that other techniques for manufacturing the core may be used consistent with the present invention, however.

The glass fusion core is an example of Photonic Crystal Fiber (PCF) technology of the type known in the art. Because of the presence of holes in the glass, the PCFs are also called"holey fibers". This is a growing commercial technology whose applications are just being realized. See, e. g. , R. E. Kristiansen, SPIE, OE Magazine, June, 2002, p. 25,"Guiding Light with Holey Fibers-tutorial"which is incorporated herein by reference in its entirety.

Holey fibers provide revolutionary optical characteristics such as for example single-mode operation from the UV to IR spectral regions. The fibers have large mode areas with hollow core diameters greater than 20 microns. Associated with these large areas are numerical apertures (NA) that can reach values of 0.9. This equates to large laser acceptance angles, and high tolerance laser coupling. Dispersion properties can be easily adjusted, and the laser power conducting capacity far exceeds that of conventional fibers. The holey fibers have been shown to be excellent conduits for high power laser energy. Unlike earlier single mode fibers with solid cores that were highly dependent on few material parameters, the PCF represent a highly engineered microstructure, with numerous free parameters to alter optical characteristics. Quite unexpected, the PCF exhibit band-gaps with forbidden frequency zones. The presence of hollow cores in single mode operation advantageously negates the damaging effects of femto-second laser radiation on solid glass cores as in older single mode fibers.

The production of various types of holey fibers is well known, and described for example in U. S. Patent No. 6,577, 801 to Broderick, et al. issued June 10,2003 entitled "Holey optical fibers" ; U. S. Patent No. 5,802, 236 to DiGiovanni, et al. issued September 1, 1998 entitled"Article comprising a micro-structured optical fiber, and method of making such fiber" ; U. S. Patent Application Publication No. 20020118937 to Broderick, et al. published August 29,2002 entitled"Holey optical fibres" ; and U. S. Patent No. 6,661, 957 to Levenson, et al. issued December 9,2003 entitled"Diffusion barriers for holey fibers", each of which are incorporated herein by reference in their entirety.

Referring now to Fig. 3, a first embodiment of the fusion core of the present invention is shown and generally designated 100. The fusion core 100 includes a body 102 formed with a set of four (4) center hollow cores, or lumens, 104, and surrounded by eight (8) larger diameter hollow cores 106. A series of smaller diameter hollow cores 108 may be formed in body 102 such that body 102 is substantially filled with hollow cores.

In one embodiment of the invention, the aforementioned core is fabricated from a unitary block of glass as opposed to individual fibers. Specifically, a femto-second or other laser under computer control may be used to"etch"or form the aforementioned containment channels (tapered or otherwise) into the block, such processing methods being well known in the art. It will be appreciated that while a"glass"block is used in this embodiment, other suitable materials, such as polymers or even ceramics, may be used in this capacity.

From Fig. 3, it is also to be appreciated that hollow cores 104,106, and 108 formed with fusion core 100 may be placed in a variety of configurations. For example, a single hollow core, such as hollow core 110 having a larger diameter, may be formed in place of center hollow cores 104. While several examples of configurations of hollow core fibers for the present invention will be discussed herein, such examples are merely exemplary of preferred embodiments, and no limitations as to the particular positioning, relationships, sizes or quantity of hollow cores are to be inferred. Also, the geometric pattern of holes is meant to be indicative of the final structure, but not exact. Likewise, the core dimensions of 10-20 microns in this embodiment are only approximate and in no way limiting of the invention.

The fusion core 100 receives an optical radiation source in a first direction 120, such as laser pulses 122 and 124. In a preferred embodiment, the laser pulses 122 and 124 have durations 126 and 128 of approximately 10-15 seconds, although shorter or longer pulses may be used within the limitations of causing sufficient energy influx to the core to cause fusion. See e. g. ,"Relativistic Laser-Plasma Interactions", Donald Umstadter, Univ. of Michigan, Journal of Physics D: Applied Physics (36) 2003 R151-R165, incorporated herein by reference in its entirety, wherein a high power petawatt (1015 W/cm2) laser is used to accelerate beams of electrons and protons to MEV energies in the space of short (micron) distances, and their use in igniting thermonuclear fusion, as well as the production of neutrons and positrons.

While pulses 122 and 124 have be shown to have substantially similar durations 126 and 128, it is to be appreciated that this is merely indicative of a preferred embodiment, and that any duration is contemplated herein, including but not limited to constant radiation sources, those having a varied pulse length or duration, or radiation sources having single pulses, muliple pulses, or pulses that are regularly or irregularly spaced.

Any number of laser energy sources can be used with the present invention. One preferred source comprises so-called"femto-second"lasers, which are well known in the laser arts. See, e. g. , U. S. Patent No. 5,400, 350 to Galvanauskas issued March 21,1995 entitled"Method and apparatus for generating high energy ultrashort pulses", and U. S.

Patent No. 5,377, 043 to Pelouch, et al. issued December 27, 1994 entitled"Ti : sapphire- pumped high repetition rate femtosecond optical parametric oscillator", both of which are incorporated herein by reference in their entirety. Such lasers are available from a number of commercial sources, such as Del Mar Ventures of San Diego, CA. In the illustrated embodiment, laser energy wavelengths on the order of between 1.2 and 0.1 micron are used, although it will be recognized that other wavelengths (including into the deep UV or X-ray regions) can be used in certain applications.

The laser pulses 122 and 124 may be striking body 102 normal to fiber cores 104, 106 and 108, and 110, along axis 129. Alternatively, laser pulses 122 and 124 may strike the body at an angle 130 along alternate axis 131. The maximum value of this angle may vary as a function of fiber geometry, materials, and other factors. As a result of this tolerance in acceptance angle of the fusion core 100, there is advantageously less concern for precise alignment that is often the case when directing laser beams into conventional solid core single-mode optical fibers. However, somewhat precise alignment between the fiber and the laser energy source (i. e. , the incident laser energy wavefront) does couple a maximal amount of energy into the fiber. One method of addressing this issue is to use holey fibers with a hollow core or cores and large numerical aperture (NA), e. g. , on the order of 0.7-0. 9, thereby allowing easy coupling of"focused", high intensity femto-second laser pulses, into the core with low loss. The holey fiber then permits the propagation of the high intensity laser pulse through the rest of the hollow fiber with low loss and no core damage, as well as permitting the laser pulse to interact with fusion fuel such as deuterium gas.

Such large NA fibers can be coupled to the laser using any number of approaches, including for example the use of a lens or other focusing apparatus (e. g. prism, parabolic reflector, or the like) disposed at the front end of the fiber (see Fig. 3A). Where an optical lens or prism is used, only certain power levels of incident energy can be used since the lens can literally be melted through the application of too high a power. For example, incident power densities of roughly 1015 W/Cm2 present an approximate upper limit when using conventional glass-based lenses, although other materials may be used as well. The airspace between the lens 150 and the ingress of the fiber 152 can also be evacuated of air or other impurities if desired, in order to mitigate any diffractive or other effects on beam propagation. The position of the lens (or lenses, where a series or parallel arrangement is used) can also be varied such that the focal length couples properly with the fiber; this parameter can even be adjusted during operation to achieve optimal performance or one or more desired behaviors. Furthermore, the focal point of the lens can be varied within the fiber interior channel (e. g. , by slightly tilting the plane of the lens off-axis) in order to focus the laser energy preferentially at one point or side of the fiber, such as to compensate for fiber imperfections, uneven fuel burn or distribution, or the effects of an external field which is not uniform on the fiber.

In another configuration (Fig. 3B), a tapered region 160 is disposed at the ingress of the fiber 152, whether part of the fiber itself or alternatively comprising a different component mated or otherwise coupled to the fiber. In this fashion, higher energy incident laser energy (e. g., 1019 W/cm2) can be directly coupled into the fiber, also without perfect alignment for the wavefront and the fiber core aperture. Hence, the taper region acts akin to a funnel, directing the incident energy generally into the fiber wherein the high NA allows the directed energy to be substantially coupled into the interior of the fiber.

Referring now to Fig. 4, an alternative embodiment of the fusion core of the present invention is shown and generally designated 200. The fusion core 200 includes a group of four central hollow fibers 202 each formed with a hollow core 204, and surrounded by a series of outer hollow fibers 206 each formed with a hollow core 208.

Radiation is directed toward the fusion core 200 in a first direction 210, such as an incoming radiation pulse 212. For discussion purposes, this radiation pulse 212 has been represented as a series of parallel radiation sources 214, although this is not required. Each of these radiation sources 214 enters the hollow cores 204 and 208 to provide a radiation energy level within the hollow cores of fibers 202 and 206.

In a preferred embodiment, the radiation energy level of pulse 212 is on the order of 1015_1016 watts/cm2. Assuming this value, the radiation energy level within any fiber is approximately the same (at least at the ingress to the fiber before any taper or mode coupling occurs). However, due to the positioning of the fibers 202 and 206 such that portions of the side walls are in contact, a portion of the radiation energy within the outer fibers 206 will mode-couple into the cores 204 of the inner fibers 202. This coupling will effectively increase the radiation energy level within the inner optical fibers 202. The coupling effect is shown with dashed arrows 220 passing from the core 208 of outer fibers 206 to the cores 204 of inner fibers 202. Fibers exhibiting such coupling are commercially available from a number of sources, such as BlazePhotonics Ltd of the United Kingdom.

Referring again to Figs. 3 and 4, the illumination of the glass fusion cores is in the exemplary embodiment conducted with femto-second laser pulses. The pulse laser illumination strikes the glass, preferably but not necessarily, normally over a region containing the 4 holes 104 with solid deuterium fuel (not shown in Fig. 4), surrounded by 8 empty, but larger holes 106. The intensity of the radiation source is adjusted below the fiber (e. g. glass) damage threshold, but increases through concentration and"mode-coupling" within the core as discussed above. In this regard, fibers with different physical characteristics; e. g. , different optical or refractive indices, damage thresholds, physical geometries (such as cross-sectional shapes and tapers) can be used for the inner and outer "tubes"if desired. Such physical variations can be used for example to increase the longevity of the inner tubes, to selectively"steer"the mode-coupled energy from the outer fibers to the inner fibers, etc.

In one embodiment, the 4 central holes are tapered down, to concentrate and increase the laser intensity to a value greater than 10l8 watts/cm2. Because the surrounding 8 holes 106 are in close contact with the inner 4 holes 104, some laser energy transfers from holes 106 to holes 104 through directional mode coupling.

It is noted, however, that even in the absence of tapering, sufficient energy density for fusion can be achieved even with sub-sufficient power density at the ingress of the fiber due to one or both of (i)"self-focusing"of the laser energy by the plasma during pulse propagation, and (ii) mode-coupling between fibers. See, e. g. ,"Propagation dynamics of femtosecond laser pulses in hollow fiber filled with Argon", Nurhuda, M. et al, RIKEN Review No. 49 (Nov. 2002), incorporated herein by reference in its entirety, wherein a peak intensity as high as 2X that of the input peak intensity was observed due to"refocusing"of the laser pulses at a distance of 12 cm.

The central group of 4 holes 104 may contain, for example, a fuel of deuterated palladium (D-Pd). The solid D-Pd fuel is in the form of thin films deposited onto the walls of the fiber holes, or otherwise introduced into the lumen as discussed elsewhere herein.

The fuel is subject to the laser pulses that directly enter the holes 104, and to the laser energy that enters from the surrounding 8 holes 106, through mode coupling.

It is known that high intensity (e. g. , femto-second) laser pulses can destroy glass and most materials. Such lasers are in fact used to etch the interior of solid glass blocks. To use such a laser to illuminate a fusion core requires that the intensity (power density) within glass sections of the core be kept below the damage threshold for the material, or at least for substantial fractions of the operating period of the core. Maximum intensity, of 1018 watts/cm2 or higher, however, is required for the efficient field ionization of the deuterium fuel and resulting acceleration of the D ions.

This seeming paradox is advantageously solved in the illustrated embodiment by having the maximum photon intensity occur within the holes (lumen) of the core (s). In one variant, this is substantially accomplished by tapering the inner 4 holes 104 to smaller diameters, and transferring additional laser energy into them by"directional coupling" ; see, e. g., Integrated Optics, T. Tamir, Ed.,"Semiconductor Components for Monolithic Applications", E. Garmire, 243-304, Springer Verlag, New York 1975, which is incorporated by reference herein in its entirety. Such directional coupling allows energy from the outer 8 holes, or hollow fibers, 106 to be coupled preferentially into the inner fibers. With proper optical design, the directional coupling can be made over ninety percent (90%) efficient.

Substantial support exists for the ability of glass and similar fibers to sustain the high energies (i. e. , peta-watt and above) associated with femto-second and other high- energy lasers without damage. See, e. g.,"Breakthrough Brings Laser Light to New Regions of the Spectrum", National Science Foundation Release 03-01 dated Jan. 2,2003, (citing Jan 2,2004 issue of Nature, by S. Backus and R. Bartels of Univ. of Colorado), both incorporated herein by reference in their entirety, wherein a femto-second laser is fired directly into the core of a hollow optical fiber waveguide to produce a tightly collimated EUV light source. The fiber core was filled with Argon gas, which was turned into a UV radiating plasma. The fiber hollow core was also a"modulated, hollow glass tube", and the wall modulations (referred to as"speed bumps") substantially survived the laser pulses without significant damage. See also"Hollow Fiber Carries Megawatt Pulses", Sept. 18 2003 issue of Optics. org (also reported at Science 301,1702), incorporated herein by reference in its entirety, wherein transmitted 75 ps pulse of 5.5 MW in a Xenon-filled hollow core holey fiber is demonstrated. In this reference, the holey fiber (hollow core) sustains peak powers on the order of 1000 times those of conventional single-mode fibers (solid core).

As yet further support for this proposition, see"Ions Generate 5-nm X-Rays",.

Photonics Spectra Magazine, February 2004, p. 24 (citing Jan 23,2004 issue of Physical Review Letters from the Univ. of Colorado), both incorporated herein by reference in their entirety, wherein a peta-watt laser pulse of intensity 1. 3 x 1015 w/cm2 was injected into a hollow core fiber (with modulated core) filled with pressurized argon to generate X-rays.

The fiber survived this exposure, and appeared to be able to sustain even higher laser intensities.

It will further be recognized that individual ones of the hollow fibers need not be used during each laser pulse. For example, in one alternative embodiment, the laser excitation energy pulses are directed at only a subset of the relevant fibers within the core per interval of time. In this fashion, the fibers undergoing fusion are rotated as a function of time, so as to mitigate secondary thermal effects, mitigate reverse mode-coupling between the center and outer cores, and so forth. In yet another embodiment, the laser energy introduced to each hollow fiber channel (or group thereof) is"tuned"in terms of intensity and/or wavelength in order to optimize performance of the core as a whole, or compensate for asymmetries or variations in energy/plasma density. Myriad other variations on the basic concept of introducing laser energy into a hollow channel disclosed herein will be appreciated by those of ordinary skill provided this disclosure.

In another embodiment, an"insulating plasma"can be generated within certain parts of the lumen (e. g. , those proximate to the wall of the fiber). In one embodiment, a Hafnium Dioxide (Hf02) material is disposed on the interior surfaces of the fiber channel, such as via a CVD or other deposition process, although it may also be introduced via impregnation into the, wall, or via diffusion through the wall or ports formed in the wall as described elsewhere herein. This material can be combined with others (e. g. , deuterated palladium, etc. ) if desired, or disposed in a discrete layer or region of the interior surface of the fiber.

As is known (see, e. g.,"Petawatt laser opens new realm of plasma physics", OE Report 168, SPIE Web, December 1997 {citing D. Pennington, LLNL}, incorporated herein by reference in its entirety), the HfO2 forms a plasma when irradiated with sufficient energy intensity, to the point of becoming highly reflective of the incident laser energy at power densities greater than approximately 2E014 W/cm2. Accordingly, when the incident and/or mode coupled energy is introduced into the fiber lumen, the Hf02 experiences sufficient power density to form a highly reflective plasma"coating"or film on the inside surfaces of the fiber, in essence a plasma ring within the lumen which also further acts to"self-focus" the laser energy. This provides a number of benefits, including reducing leakage of energy from the fiber through the walls, and even some degree of insulation of the fiber walls from the high-intensity laser energy propagating through the fiber lumen.

The directional coupling process is shown schematically with dashed arrows 220 in Fig. 4. The laser illuminated central portion of the fusion core with the 4 tapered fuel fibers is illustrated. The large vertical arrows 214 represent the portion of a femto-second pulse entering all the hollow fibers, with intensity below the damage threshold. The smaller horizontal arrows 220 shown in dashed lines represent the directional coupling of laser energy into the central D-Pd filled fibers 204. It will be recognized by those of ordinary skill that other geometries can be used, such as for example where the D-Pd filled fibers surround larger hollow fibers, and the directional coupling is from the inside out.

Alternatively, the"fueled"fibers can be interspersed with the other fibers (e. g., heterogeneous rings) so that coupling occurs not only between the inner and outer"rings" of fibers, but also circumferentially within a ring. More than two rings can be used as well, myriad other such variations being possible.

It will also be recognized that the illustrated embodiments using small diameter hollow-core fibers have another salient advantage relating to their scalability. Specifically, one can in theory utilize a single minute fiber to produce fusion energy; however, that single fiber will have limited installed fuel (or limited uptake of fuel inserted form an external source such as diffusing through the porous fiber). However, by simply adding more similar fibers to the array (and energy sources as required), the energy output can be scaled incrementally. Using larger diameter fibers (and/or more fibers) also scales up the power. Hence, the present invention can be practiced on anything ranging from an extremely small scale to a very large scale, depending on fiber and core sizes and geometries. Multiple cores can also be used together to form even larger arrays of fibers.

Neutron and/or gamma reflectors can also be controllably interposed between the fibers or arrays to control the lateral leakage from the fibers/arrays to their neighbors, much like a control rod controls localized neutron flux within a fission core, the distinction here being that no criticality issues exist with the present invention. Such leakage control may be desirable to control, e. g. , material damage (e. g. , neutron embrittlement), energy leakage into adjacent fibers, etc. For example, materials such as Beryllium, Deuterium Oxide (do), 58Ni/Mo, and/or water can be used to reflect neutrons. Furthermore, the materials can be chosen to selectively taiior the reflection coefficient (fraction) as a function of incident neutron energy, such as where it is desired to allow thermal neutrons to pass substantially unimpeded, yet block fast neutrons (or vice-versa).

Alternatively, however, the neutron or other particle/wave leakage between fibers may be used to reduce the net percentage leakage of energy from the core as a whole. As is well known, as the number of energy radiating"pipes"is increased within a given geometric proximity of one another, the ratio of lost energy to generated energy is reduced, since the surface area (or radius in two dimensions) does not increase as fast as the rate of energy production, especially where mode-coupling of the type previously described herein is present. Hence, in certain configurations, the core of the present invention can be made more efficient through aggregation of a number of different fibers disposed proximate to one another.

It will be recognized that all the hollow fiber configurations discussed herein can also be"potted"or encapsulated in an encapsulant (such as for example a polycarbonate or other polymer, elastomer, or even metal or alloy) of various shapes. This includes, without limitation, encapsulating the fibers as individual strands, as well as encapsulating a fiber "block"such as shown in Fig. 3. For example, the exterior of the fiber core block of Fig. 3 could be encapsulated in a lead shield doped with beryllium or another neutron reflector.

The recirculating architectures of Figs. 12-13 may also be encapsulated if desired. This encapsulation protects the comparatively fragile glass fiber technology from accidental damage, makes it easier to position the modules, absorbs leaking neutrons, and make the components safer to handle when in operation. The plastic potting or encapsulation can also include dopants or other forms of materials (such as lead sheets or foil in appropriate locations to absorb X-rays and gamma rays or reflect neutrons), and thus make the module safer to handle or use in non-laboratory applications.

Also, the fibers may be coated with a metallic material if desired, such as aluminum ; see, e. g. ,"Light Constructions: New fabrication technique optimizes excimer-laser light", S. Bains, OE Reports 180, SPIE Web, December 1998, wherein a mechanism for coating optical conduits such as fibers with aluminum using CVD as developed by Tohoku Univ. of Sendai, Japan; and"Delivery of F2-excimer laser light by aluminum hollow fibers" ; Matsuura, Y. et al ; Optics Express Vol. 257, June 19,2000, both incorporated herein by reference in their entirety.

It will be appreciated that other means of controlling and/or intensifying the laser energy or mode-coupling between fibers may be used consistent with the invention. For example, the use of glass dopants that induce laser energy amplification, reflection, or redirection may be employed within one or more fibers of the core, or within the material interposed in the interstices of the fibers. In one embodiment, the present invention envisages a fiber"bundle"such as that of Figs. 4 or 10 herein, with the interstitial regions being filled with a controllably varied chemical solution, the solution being used as a fuel, to control other properties, heat control, etc. The constituents of the solution may be varied as a function of time or other parameters to effectuate specific operational objectives, such as increased/decreased mode coupling between fibers, neutron reflection or absorption, gamma or X-ray absorption, fuel concentration, fuel injection rate, refraction of the mode- coupled energy, etc. Such a liquid control mechanism may also be circulated or selectively purged and replaced if desired.

For example, one variant of the invention uses a constant recirculation system wherein the volumetric density of interstitial"fluid" (which may also comprise at least part gaseous phase material) is controlled by selectively cooling or heating the fluid before introduction into the core. In this fashion, gamma, X-ray, neutron, and/or mode-coupled laser energy can be selectively moderated or reflected. In another embodiment, the interstitial fluid mix is varied on the fly, such as where the fuel concentration is increased to provide a higher core fuel density. Similarly, the pressure of the fluid can be controlled, thereby controlling the rate at which fuel is injected into the fibers via through-wall ports such as those described elsewhere herein.

It will also be appreciated that the foregoing liquid control scheme can be applied on a per-fiber basis if desired, such as where each fiber is surrounded at least partly by an annulus or chamber which can be separated from other fibers (or groups of fibers) of the core in general. Heterogeneous application of"control fluids"can be made across the core, much as different control rod positions and/or fuel densities are used in a conventional fission reactor to control the thermal and fast neutron longitudinal and radial flux profiles, so as to e. g., control power density and hence fuel burn rate. This approach allows for the balancing of the core power density, which may be required to control the thermal (temperature) profile across the core to prevent damage thereto (i. e. , avoiding or mitigating "hot spots").

Similarly, as a logical extension thereof, the fuels concentrations and/or types can be varied on a per-fiber or per-group basis of desired in order to effectuate any of the foregoing objectives. For example, in those areas where leakage of mode-coupling energy is greater (such as at the periphery of the core), the fuel density and or laser pulse intensity can be varied to balance the core power profile and/or control temperature, etc. This fuel control can be accomplished by design (i. e. , before operation), or"on the fly"using, e. g. , the liquid or gaseous system previously described wherein fuel concentration, constituency, temperature, etc. can be varied as a function of time.

It will also be appreciated that mode-coupling between fibers can be selectively controlled, and can comprise uni-direction or bi-direction coupling. For example, with no control mechanism, mode-coupling can occur both in and out of a give fiber. However, through the selective application of polarizing materials or coating (or other approaches that limit the direction of wave propagation to one direction only), mode coupling can be made to occur predominantly only either into or out of a fiber, but not both.

Referring now to Fig. 5, an alternative embodiment of the fusion core of the present invention is shown and generally designated 300. The fusion core 300 includes a fiber 302 formed with a hollow core 304 and having an input end 306 and an output end 308. A fusion fuel 310, such as a deuterium fuel, may be coated or sprayed on the walls of fiber 302, or otherwise introduced such as via diffusion through the fiber walls. As yet another option, the fuel may comprise one or more elements (e. g. , palladium wires) disposed centrally or in an array within the fiber lumen.

A radiation source approaches the fusion core 300 in a first direction 312, such as laser pulses 314,316, and 318. As shown, these pulses may be focused in a taper angle 320 (shown in dashed lines) in order to focus concentrated radiation energy on input end 306.

These pulses enter the input end 306 of the fiber 302 and provide optical energy 332 at an energy level sufficient to activate and react with the fusion fuel 310. As a result of this interaction, a fusion reaction occurs resulting in the formation of a plasma beam 334 exiting the output end 308 of the fiber 302.

The fusion core 300 may optionally be formed with an input shield 322 and an output shield 324 (shown in dashed lines). These shields 322 and 324 provide for the sealing of the fusion core to retain any fusion fuel therein. This is particularly useful in situations where the fusion fuel 310 is not a solid, such as when a powder, liquid, or vapor 311, is being used as the fusion fuel, and/or where it is desired to exclude exterior environments (e. g. , air) or contaminants from the interior of the fiber, such as where the core is at least initially maintained at a relative vacuum, or is purged with a gas such as nitrogen or argon. These shields are, in a preferred embodiment, made from a material that is optically transparent to the incoming radiation, although other configurations may be used depending on the desired properties.

In Fig. 5, the radiation energy that is mode-coupled into fiber 302 is shown with arrows 330. In this configuration, radiation energy is mode-coupled into the fiber 302 thereby increasing the energy level within the fiber to a level that is sufficient to initiate the fusion reaction with the fusion fuel 310. Also from this Figure, a tapering of the fiber 302 is shown thereby increasing the radiation energy level as the radiation propagates from the input end 306 to the output end 308.

The relative success of Ditmire's 1999 experiment at LLNL with laser fusion of deuterium, was in large part due to the use of fuel in the form of frozen deuterium clusters and not deuterium gas. These clusters contain D atoms in close proximity (approximately, I Angstrom). The short distances increase the probability that energetic D ions will fuse with adjacent ones. Each frozen cluster has thousands of atoms. Since each D-D fusion produces a characteristic energy neutron, the numbers of these neutrons detected indicate that 1-10 clusters took part in the initial Ditmire fusion ignition experiments.

The close proximity of D atoms in the fuel is an important consideration for the success of the fusion ignition process. In earlier experiments on inertial confinement, close proximity was achieved with a double pulse laser. The first pulse compresses the fuel with a powerful shock wave, and shortens the atomic distances. The second pulse accelerates the D ions into the now closer D atoms for the fusion ignition. This"double kick"is another avenue to achieving the necessary conditions for fusion.

However, frozen deuterium clusters may not be the best fuel. Specifically, they have to be produced by adiabatic expansion of deuterium gas into a vacuum, and if not used immediately, they are rapidly"thermalized"back into a gas. The small atomic clusters, and their small numbers within the focused laser beam, keep the critical ion density at low values. The short time associated with maximum laser intensity at the cluster positions, also reduces the critical confinement time. The hollow fiber approach of the present invention using fueled fibers containing D-Pd, increases both of these parameters significantly. More fusion fuel is incorporated, and a fiber-confined laser beam is used to maintain maximum laser intensity over a longer distance.

In the exemplary embodiment, a choice for a stable solid fuel is deuterated palladium (D-Pd), otherwise known as a"halide"or"deuteride". Palladium is a metal in the Platinum family, with an extraordinary propensity to absorb hydrogen and its heavy isotope deuterium. At maximum deuterium"loading", there are equal numbers of Pd and D atoms in the material. The palladium actually swells in size visually, as deuterium is added.

Palladium is made into a negative cathode, and positively charged deuterium ions are made to strike it. X-ray measurements of the material show that the inter-deuterium distances are on the order of 1 Angstrom. In other words, they are very close to the inter-atomic deuterium distances present in frozen deuterium clusters. However, unlike frozen clusters, they are stable and can be used in air and at room temperatures. As will be recognized by those of ordinary skill, there are other deuterides that can be used similarly, including without limitation those of Ni, Li, Pt and Ti. The use of Li deuteride is particularly relevant, in light of its use in producing tritium fuel with neutron bombardment.

In one embodiment of the present invention, the palladium is sputtered onto the inside walls of the hollow fibers while they are a preform. The palladium is a ductile metal and can survive the drawing down of the glass fiber to fusion core dimensions, without detaching from the glass. In another embodiment, a vacuum or vapor deposition process of the type well known in the art is used to deposit the fuel onto the fiber walls.

It is also feasible to incorporate the palladium (or similar) into the fiber material itself during fabrication. Furthermore, it will be recognized that the palladium may be deposited or formed on the walls of the fiber in a heterogeneous fashion; i. e. , mixed with one or more other substances such as Lithium, which may provide complementary or desired properties, such as increased adhesion during drawing down, neutron moderation/reflection/absorption, etc.

The process of loading deuterium into palladium can be accomplished by, e. g. , ion bombardment. The palladium is made into a negative cathode and bombarded by positive charged deuterium ions while inside the fiber. Resistance measurements of the Pd can determine maximum loading. The maximum deuterium loading factors of Ni, Pt, and Ti, however, are less than palladium. However, it is envisaged that more efficient methods for deuterium or other isotope loading into palladium or other materials may exist or will be introduced over time, thereby further increasing the loading factors of these materials, the ion bombardment process being merely illustrative.

The propagation of femto-second laser pulses through the hollow core of the tapered D-Pd loaded fiber is initially shown in Fig. 5. Unlike the focused laser beam in air or vacuum shown in Fig. 1, the energy intensity of the present invention (irradiance in watts/cm2) actually increases as the laser pulses propagate down the fiber toward the output end 308. Irradiance increases due to, inter alia, the mode coupling of laser energy from adjacent fibers, self-focusing within the core plasma and the"focusing"action of the taper.

With proper design, the pulse irradiance will reach >1018 watts/cm2 inside the fiber when the D-Pd fuel is reached by the wavefront (s), or when the deuterium clusters reached after they are introduced and/or sprayed into the fiber core through the wall ports.

Referring now to Fig. 6, an alternative embodiment of the fusion core of the present invention is shown and generally designated 400. The fusion core 400 includes a fiber body 402 with an internal fiber 403 formed with a hollow core 404. Adjacent fibers 405 and 407, having hollow core 406 and 408, respectively, are formed adjacent fiber 403. The fiber 403, in a preferred embodiment as discussed above in conjunction with Fig. 5, may be formed with a fusion fuel 410 coated on the inside surface of core 404.

Radiation energy 420 is directed toward the fusion core 400. In one embodiment, radiation energy may comprise radiation having several different wavelengths, or "broadband"radiation sources. For example, in Fig. 6, radiation energy 420 includes a first radiation source 422 having a first wavelength (81), a second radiation source 424 having a second wavelength (82), and a third radiation source 426 having a third wavelength (83).

Alternatively, the spectral coherency of one or more of the lasers can be varied, such that a wider bandwidth of (less coherent) light is produced.

Radiation sources 422,424, and 426 have been represented as a series of radiation pulses 428,230, and 232 indicative of the femto-second laser pulses of one embodiment of the present invention. However, it is to be appreciated that the discussion of these radiation sources is merely exemplary, and the radiation sources may provide radiation which is continuous, all of the same wavelength, or a combination of continuous, pulsed, single or multi-wavelength radiation, either highly coherent or more spectrally distributed.

Radiation sources 422,424, and 426 pass through the shield 434 and into the cores 406,404 and 408, respectively. The radiation 424, which enters the core 404, interacts with fusion fuel 410 to create a fusion reaction and a resultant plasma/particle/EM beam 460 is formed which exits output shield 436.

Once the radiation is received within cores 406 and 408, this radiation begins its mode-coupling into core 404, as shown by arrows 450. Mode-coupling provides for the passage of radiation energy from cores 406 and 408, into fiber core 404 thereby increasing the radiation energy density within the fiber core where the fusion reaction will take place.

For example, by the introduction of additional radiation energy into core 404 through mode coupling as shown with arrows 450, a higher radiation level can be reached within the core 404. In fact, a radiation level that would otherwise be too great for the fiber to withstand if generated by a single ingress location can be achieved within the fiber core 404 with mode- coupling from adjacent fibers.

Optionally, one or more fuel ports 442 may be formed in the fiber 403 to allow the passage of additional fusion fuel from fibers 405 and 407 into fiber 403. More specifically, additional fusion fuel may be contained within the cores 406 and 408 of fibers 405 and 407 (or the interstices between the different fibers), and these fuels may be transferred into core 404 of fiber 403. As shown, the cores 404,406 and 408 may have internal pressures PI, P2, and P3, respectively. When Pl is less than P2 and P3, fusion fuel within fiber cores 406 and 408 will pass through fuel ports 442 and into core 404 where the additional fusion fuel will be combined with fuel 410 in the fusion reaction.

The outer fibers 405 and 407 may be formed with external fuel inlets 438 to provide for the introduction of additional fusion fuel 440 into cores 406 and 408. In addition, these fuel inlets 440 provide for the adjustment of the pressures P2 and P3 and the strength of the fusion reaction occurring in core 404. More specifically, by increasing pressures P2 and P3, additional fusion fuel 444 will pass through fuel ports 442 into fiber core 404 to provide a stronger fusion reaction. Conversely, by decreasing pressures P2 and P3, a decreased amount of fusion fuel 444, or perhaps no additional fuel, will be injected into core 404, thereby decreasing the strength of the fusion reaction. Using this approach, a fusion reaction of a desired intensity may be created and controlled using the present invention.

This pressure differential may also be used to control the egress of any vaporized or atomized fuel components or other materials outward from the core.

Varying degrees of field ionization will occur within the fiber's fusion fuel 410, such as D-Pd coating and D2 clusters along with"Wakefield acceleration"of D-ions, electrons, protons and other ions from the fusion and Pd. The electrons and ions are driven by, inter alia, the laser pondermotive force in the direction of the laser, or radiation source 420, down the fiber, and into further interactions with additional D-Pd and D2 fuel. The pondermotive force (photon pressure) acts much like a"snow plow", forcing the plasma and other constituents ahead of the wavefront down the fiber length, with the laser pulse performing relativistic"self focusing"within the plasma (thereby increasing the tight collimation in the direction of the laser pulses). See, e. g. ,"Amazing Power of the Petawatt", K. Walter (citing Michael Perry, Lawrence Livermore National Laboratory), Science and Technology Review, 2000, which is incorporated herein by reference in its entirety. See also"Laser-Like Beam May Break Barriers to Technological Progress", NSF Press Release 02-60 dated July 18, 2002 (citing work at the Univ. of Colorado referenced above), incorporated herein by reference in its entirety, wherein an EUV beam is generated that can produce a very small diameter high-energy laser-like beam (i. e. , several times smaller than a more common helium-neon laser and several hundred times more intense).

The fusion process within the present invention can be described as a"cascade" fusion ignition of the deuterium fuel on the inside of the fiber 403. This reaction can be further enhanced with the addition of additional D clusters or other fuel coming through other porous sections of the tapered glass fiber 403. It will also be recognized that heterogenous types of fuel can be used, such as where different portions of the fiber interior are coated with different types of fuel, and/or"downstream"injection of a fuel different from that upstream on the fiber walls (or injected upstream) is used.

At all points in the interaction, a strong radiation field is present. For relativistic plasma moving down a fiber, the laser pulse remains in close proximity to the plasma. This is in contrast to previous cluster ignition methods, in which a reaction occurs in only a small laser focus region, measured in microns. Advantageously, the propagating laser field 420 (and associated EM fields) acts to cause further ionization, and help confine the plasma into a ring or shaped region within the fiber core 404 and away from the glass walls, the plasma moving in the laser direction 424.

In a preferred embodiment, the laser radiation will self-focus substantially along the axis 470 of the fiber 404 and propagate along a central axis of ions, forming a core (or ring) of high energy, relativistic plasma that exits the fiber at its effluent channel, as shown in Figs. 5 and 6. Rather than hit the interior walls of the glass fiber 403, the plasma 460 will be highly collimated with the laser energy, and remain within the lumen, or core 404, of the fiber. Transverse plasma motion and photon motion (and to some degree neutron emission) is expected to be smaller.

In the fusion core of the present embodiment, the ion density within the core 404 is determined primarily by the entire amount of fusion fuel material, such as D-Pd and D2, inside the fiber 403. Likewise, the confinement time is determined by the laser transit of the entire length of fusion fuel 410, such as deuterium, in the fiber 403, which can be many millimeters, and even centimeters or longer in length. The Lawson factor is therefore increased by a significant amount.

Referring again to Fig. 6, it is to be appreciated that the additional deuterium fuel in the form of frozen clusters, gas and even liquid, can enter the lumen, or hollow core 404 of the tapered fiber 403 through porosity and holes 442 formed in the walls of the various glass fibers. Porous glass, such as"Vycor"is commercially available, and/or sub-micron holes can be drilled in the fiber walls with lasers using a method that is known in the art.

The walls of the fiber can also be impregnated with fuel atoms at or after manufacture such that these atoms are given up to the lumen as the temperature of the fiber wall is increased.

Furthermore, many kinds of glass can become porous to Hydrogen (including Deuterium) by simply heating the glass to temperatures between 400 degrees F and 700 degrees F. It is anticipated that the fusion reactions inside the hollow lumen of the glass fiber, will provide enough heat to raise the glass temperature to well above 400 degrees F and permit outside pressurized deuterium fuel to diffuse into the fusion reaction area.

The use of porous glass to allow"fueling"of the fusion reaction is illustrated in Fig.

6. The pressurized deuterium gas may be located within, or introduced into, the larger adjacent fibers 405 and 407, and enters the smaller D-Pd loaded fibers adiabatically, through the fuel ports 442 as a"spritz"of fuel, e. g.. frozen deuterium clusters.

The apparatus of the present embodiment permits the fusion reactions within core 404 to be continuously fueled with fusion fuel such as deuterium, and power controlled by the amount of fuel allowed to enter the fibers through the fuel ports 442. It is further envisaged that the fusion reactions can run totally with the spritz of (frozen) deuterium or other fuel, and without the Pd-D coating on the lumen walls. With larger walls, deuterium can enter as a gas or even a liquid spray of heavy water, or via other mechanisms that will be readily apparent to those of ordinary skill provided the present disclosure.

It is further recognized that the fuel may even comprise plain (i. e. , non-heavy) water, and ordinary hydrogen fusion will take place albeit with a smaller fusion cross- section than for deuterium. Under the intense radiation associated with the fiber and fuel chambers, substantial dissociation of heavy water molecules will occur, thereby forming quantities of deuterium which can then act as the fusion fuel for the core.

In another embodiment, the fuel introduction system comprises atomized or particulate form (such as a spray or stream of deuterium of a liquid solution such as atoms disposed within water) which is prayed or otherwise injected into the fiber from the ingress end just ahead of the laser pulse, such that the pondermotive force pushes or"plows"the fuel atoms into the fiber lumen.

The hollow glass fibers of the present invention may also be used in laser fusion geometries other than a"linear"geometry as previously illustrated. The fundamental concept is that glass fibers, including e. g. , the holey fibers previously described, act as wave guides for laser light or other EMR that can redirect the light into any direction by bending the fiber; and the light pressure can then force atoms, ions and particles to also undergo a change in path direction to follow the light. The shape of the fiber containing fusion plasma and laser pulses therefore advantageously becomes arbitrary. In fact, modern designs of the holey fibers have demonstrated the bending of light around 90 degree turns in an area of a few hundred square microns, thereby allowing for significant"kinks"or discontinuities in the fiber to be present if desired or required for some other design objective.

Referring now to Fig. 7, another variant of the fusion core of the present invention is shown and generally designated 500. The fusion core 500 includes a holey fiber 502 having an input end 504 and an output end 506 and formed with a lumen or hollow core 508. A radiation source, such as laser input 510 is directed at the input 504 and propagates down the hollow core 508 until striking the fusion fuel 512 positioned therein. The fusion fuel 512 is shown as a solid and positioned against the wall of lumen 508; however, it is to be appreciated that any type of fusion fuel may be contained within fiber 502, including fluid, gas, vapor, powder, or a combination thereof. The input end 504 and output end 506 may be formed with seals shown in dashed lines to, inter alia, retain any fusion fuel within the hollow core 508 of the fiber 502. As radiation 510 enters the hollow core 508, a fusion reaction occurs and creates a plasma beam 514 which exits the output end 506.

The fusion core 500 of the present invention may optionally be equipped with a source of electrical energy generally designated 516. The energy source 516 includes, for example, a current source connected to windings placed about the fiber 502. In this configuration, the current source provides a current within windings that correspondingly create a magnetic field within the fiber 502, the field increasing the energy level within the core 508. Depending on the orientation of the windings, the magnetic (B) field vector (s) can be generated in any desired direction, including longitudinally along the central axis of the fiber, or transverse thereto.

Depending on the longitudinal position of the windings, the external magnetic field can also be used as a"steering"device for charged particles within the fiber, since charged particles moving in a magnetic field will feel a force in the direction of the vector cross product of the charge velocity and the B-field, as is well known.

Further, the addition of a magnetic field within core 508 can be used to maintain the formation of a central plasma beam separated from the inside of fiber 502.

Referring now to Fig. 8, an alternative embodiment of the present invention is shown to illustrate the flexibility of the fusion core geometry. More specifically, fusion core 550 includes a fiber 552 containing a fusion fuel (not shown this Figure), and having an input end 554, and an output end 556. Radiation enters the input end 554 and reacts with the fusion fuel to create a plasma beam 562 which leaves the output end 56. Of interest in this Figure, however, is that the fiber 502 is shown as non-linear. In fact, the fusion core of the present invention is capable of other shapes other than linear, and that the presentation of the embodiment if Fig. 8 is merely exemplary of the versatility of the present invention, and no limitations as to available configuration is to be inferred. As will be described subsequently herein, myriad different core shapes are possible, including for example arced, circular, helical, elliptical, oval, or conic (or frustoconic).

In another alternative embodiment of the present invention, a fusion core may be formed with a fiber having a central hollow fiber surrounded by an array of hollow fibers having significantly smaller diameters. Generic holey fibers are created in this manner.

Referring to Fig. 9, such a fusion core is shown and generally designated 600. The fusion core 600 includes a fiber 602 formed with a central lumen, or hollow core, 604, and formed with a plurality of additional hollow cores 606 having diameters which are substantially smaller than the central hollow core 604. The fiber material 608, such as glass, provides for an optically transmissive media between the various hollow cores 604 and 606 such that radiation received in the hollow cores 606 mode-couple into the central core 604 thereby increasing the radiation level within that core. The interstices between the fibers may also be selectively evacuated if desired such as to permit diffusion of atomized, gaseous or liquid fuel (including the aforementioned carbon nanostructures) into the central region 604, to provide neutron reflection, etc.

In another embodiment of the invention, the fibers (or core"block") can be coated, such as on their inner or outer surfaces, and/or doped with a neutron reflective material such as graphite, beryllium, or even heavy water (e. g. , Deuterium Oxide) to reflect neutrons back into the hollow core region to induce additional reactions (such as with Lithium-6).

Advantageously, in one configuration, the additional fusible fuel introduced in the fiber hollow core via fiber wall porosity or holes is also used as the neutron reflector. A constant annular"thickness"of deuterium-based fusible fuel present around the outer surface of the fiber acts as both a fuel source and a neutron reflector. This configuration also has control ramifications; i. e. , in the self-sustaining (non-pumped) mode of operation, expiration of the external fuel source coincides with degradation of the neutron reflection coefficient of the apparatus, thereby in effect allowing further energy to bleed from the hollow core. Stated simply, when the external fuel runs out, so does the neutron reflectivity, thereby resulting in a self-initiating shutdown. Alternatively, the density or thickness of the reflector material may be used as a control mechanism.

In another exemplary embodiment, selectively movable neutron reflecting elements (akin to control rods in a fission system) are used to allow control of the neutron reflection characteristics of the core as a whole, or for individual core fibers or groups of fibers.

Mechanism for providing such control are readily fashioned by those of ordinary skill, and accordingly are not described further herein.

Fig. 10 presents another alternative embodiment of the fusion core of the present invention and is generally designated 650. The fusion core 650 of Fig. 10 includes multiple fibers 602 (of the type shown in Fig. 9), and grouped together to form a bundle. The fibers 602 are attached or formed together using an optically transmissive material, such as glass 652, although other materials may be used as desired. In this configuration, the radiation energy levels within fiber cores 604 will increase due to the radiation mode-coupled from adjacent fibers 602. As with the embodiment of Fig. 9, the interstices of the bundle can be used to control mode coupling, store and/or introduce additional fuel, provide cooling to the fibers (and draw away thermal energy), act as a neutron/energy reflector, or provide various other functions.

Referring now to Fig. 11, another alternative embodiment of the fusion core of the present invention is shown and generally designated 700. The fusion core 700 includes a fiber 702 having a central lumen or hollow core 704. The central hollow core 704 is axially surrounded with a sleeve 706 of optical fiber material, such as glass or quartz, having a first index of refraction. A second sleeve 708 of optical fiber material, such as glass, having a second index of refraction axially encases the first sleeve 706. Similarly, a third sleeve 710 of optical fiber material, such as glass, having a third index of refraction axially encases the second sleeve 708. Finally, a fourth sleeve 712 of optical fiber material axially encases the third sleeve 710. It will be appreciated that more or less layers or sleeves may be used, the present configuration being merely illustrative.

By choosing the indices of refraction appropriately, it is possible that radiation striking the input end 713 of fiber 702 is focused inward toward the center 704 of the core.

As is known, the interface of two materials of varying index of refraction will produce a bend or change in direction of propagation via Snell's law. Hence, by choosing materials with progressively larger or smaller indices of refraction, the incident light energy coupled into the various layers can be selectively"focused"or dissipated, respectively, the light changing direction inward (radially) or outward at each interface between sleeves.

Furthermore, the use of various materials having different indices of refraction allows for multiple propagation modes within the fiber. This approach may be desirable where temporal distortion or chromatic dispersion of the laser pulses as they propagate down the fiber can be tolerated.

The fiber 702 of fusion core 700 may be formed with a number of fuel input ports 714 for the introduction of fusion fuel into hollow core 704 as discussed above in conjunction with Fig. 6. It will be appreciated that while Fig. 11 illustrates a single row of circumferentially disposed ports, literally any formation or combination of ports can be used, including for example being disposed in a plurality of circumferential rings down at least a portion of the length of the fiber, being disposed in one or more linear arrays down the length of the fiber, being disposed according to a geometric parameter (i. e. , the ports increasing or decreasing in diameter as a function of position, arc, etc. ), or being configured so as to be selectively permeable under different physical conditions. Myriad other configurations will be recognized by those of ordinary skill. Means for controlling the introduction of fuel into the containment fiber (s) are well known in the mechanical arts, and accordingly not described further herein.

It will also be recognized that the fiber wall holes and porosity used to admit fuel can serve another important function, which is to cool the hot fibers. Heated fibers will cause the liquid (e. g. , water) fuel to boil and form vapor, which not only enters the hollow fiber core as a fuel, but also lowers the glass temperature. Hence, in one exemplary embodiment, the fiber is surrounded by one or more channels (to include even a concentric fiber or other chamber of larger radius). Fuel (e. g. , liquid, gas, etc. ) is contained in the channel (s) such that it is in communication with the outer surface of the fusion core fiber.

As the fiber is heated by the ongoing fusion within the fiber lumen, heat is transferred to the liquid or gas, thereby increasing its pressure within the closed constant-volume channel (s).

As pressure builds, more of the liquid or gas fuel is diffused into the porous fiber wall, thereby inserting more fuel into the fiber lumen. The porosity of the fiber can also be controlled or selected such that only vapor phase fuel can be passed through the fiber wall, in effect using a fuel"boiler"akin to a steam generator in the secondary plant of a conventional fission PWR.

In light of the fiber's ability to steer the optical radiation and resultant plasma beam as previously described herein, the embodiment shown in Fig. 12 includes one or more hollow fiber fusion cores of glass or other material (to include the multi-sleeved variant of Fig. I 1 if desired) that have the shape of a toroid (closed circle) with ports to allow laser light to enter and fusion plasma to exit. This apparatus of Fig. 12 presents a"re- circulation"technique, similar to the prior art Tokamak, which greatly increases the ion particle density inside the fiber lumen, and greatly increases the containment time, both critical components in the Lawson criteria. However, a salient distinction between the prior art Tokamak device and the fiber fusion core of the present invention is that the fiber fusion core (including even the femto-second laser) will fit onto a table top, while the Tokamak requires a building-size structure.

Rather than supply outside magnetic fields to force the plasma particles into circular and re-circulant paths as in the Tokamak, the laser photon electromagnetic fields generated by the present invention provide the necessary pondermotive force to keep the plasma contained within the fiber lumen and hence propagating in a circle trajectory. Fusion fuel can be continuously or intermittently fed into the circular fiber trough the porosity of the glass, and mode coupling occurring at the laser injection port (s) continuously transfers new laser pulses into the circular fusion fiber core. Hence, the apparatus of Fig. 12 can be operated for relatively lengthy durations, up to even continuous operation under the proper conditions. In order to support long-term operation, other facilities may be required, however, including a cooling medium to dissipate thermal heat of the fiber which may become deleterious to the fiber material or other components after a few seconds of sustained operation.

Another salient benefit of the fiber fusion core of the present invention is the retention of a substantial fraction of the radiation generated from accelerated plasma charges within the core of the fiber and the fusion process in general. As is known, a wide variety of subatomic species (e. g. , neutron, protons, electrons, neutrinos, and even fractional or elemental particles such as quarks) and electromagnetic radiation (including e. g., X-rays, gamma rays, UV, visible light, etc. ) can be emitted from a fusion event under proper circumstances. The pondermotive forces generated by the traveling laser wavefront (s) and associated magnetic fields in effect form a containment"sleeve"inside the fiber, tending to deflect any escape of these species and EMR Certain particles such as neutrinos will be largely unaffected by the pondermotive sleeve; as will (albeit to a lesser degree) neutrons.

While no practical neutrino deflection or reflection apparatus can be applied, various schemes and materials which reflect neutrons ranging from thermal to fast energy can be used, as described in greater detail subsequently herein. The formation of the sleeve, with or without the neutron reflector, greatly enhances the energy density within the fiber. In a typical Tokamak reactor, the radiated photon energy (and a portion of the neutron energy) is substantially lost.

Radiated light (e. g. , Bremsstrahlung or breaking radiation) from accelerated plasma charges in the core are also confined to the core by the single mode holey fibers and not lost as in the prior art Tokamak. Rather, they add their pondermotive forces to that of the introduced laser pulses, and under certain circumstances may sustain the plasma reactions with the laser turned off (at least intermittently). The amount of this radiated light increases dramatically as the Z4 value of the ion species in the plasma, and can be a significant part of the radiation field within the fiber.

A significant fraction of the uncharged particles emanated from the various reactions occurring within the core (such as the neutron) will be held in fiber confinement via the mechanisms of a) photon pondermotive forces (photon pressure), b) reflection off the interior walls of the fiber core, and c) collisions with other particles such as electrons and protons moving axially down the fiber core (i. e. , conservation of linear momentum and energy). Use of neutron reflectors (such as described elsewhere herein) further increases the fraction of neutrons emitted from the fiber effluent.

The relative spatial efficiency of the fiber core for neutron ejection (flux) within the effluent solid angle 0 can be related to the total neutron flux created within the core: n = Ne/Nt Eqn. (7) where: n = Efficiency Ne = Total No. of neutrons (all energies) emitted within solid angle NT = Total No. of neutrons (all energies) emitted within solid angle 4 The efficiency n represents simply a measure of how many neutrons are emitted with the desired effluent solid angle as compared to the total number emitted over all solid angles within the same time period. The greater the efficiency, the smaller the leakage of neutrons through the walls of the fiber, the other end of the fiber core, etc. It will be appreciated that simply by virtue of the physics of the fusion process disclosed herein, including the directionality of the incident laser energy, the fiber geometry, presence of pondermotive forces, etc. , certain solid angles are preferred (i. e. , have higher probabilities of neutrons being ejected within those angles with all else being equal). Hence, in the linear fiber/core geometry previously described herein, the solid angle centered on-axis in the downstream (effluent) direction would naturally have the highest neutron flux density, whereas the opposing solid angle ("upstream") may have the fewest flux due to e. g. , pondermotive forces. Hence, optimal or highest efficiency for such a geometry will always be achieved when the solid angle is chosen on-axis in the downstream direction.

Use of a neutron reflector increases, since more neutrons are reflected back into the lumen of the fiber where they can interact with other particles, or be re-subjected to photon pressure. Such reflections also have a finite probability of direct reflection into the solid angle #.

Similar to the neutron reflector, increased pondermotive force provides a greater "restraint"or photon pressure on the neutrons, thereby lessening their lateral escape probability. Hence, as the power density of the exciting laser or EMR pulse increases, so does the pondermotive force, thereby reducing the fraction of neutrons"lost"out the fiber walls.

It will also be appreciated that varying levels of interaction between the charged particles within the lumen may occur, such as where high speed particles will exert an electrostatic force on other charged particles. However, the combination of the conserved momentum within the lumen, intense pondermotive forces, and other forces (such as any externally applied"helper"or containment fields) will be sufficient to cause the great preponderance of charged particles to also be ejected out through the solid angle of interest (i. e. , out the effluent end of the fiber lumen).

Referring more specifically to Fig. 12, an alternative embodiment of the fusion core of the present invention is shown and generally designated 800. The fusion core 800 includes a circularly shaped optical fiber 802 having an input port 804 for injecting radiation 806, and an output port 808 for ejecting plasma 810 and effluent. As will be discussed in greater detail below, radiation 806 enters the input port 804, circulates through optical fiber 802 in direction 812, and exits at the output port 808 as a plasma beam 810.

The fiber 802 of the illustrated embodiment is formed with a series of fuel inlets 814 which allow fusion fuel 816 to pass from a region of higher pressure Pl to a region of lower pressure P2 within the hollow core of fiber 802. This pressure gradient between P, and P2 may be adjusted to control the volume of fusion fuel which enters fiber 802.

An output switch 820 (shown in dashed lines) may be used to perturb the plasma beam circulating through fiber 802 in order for all or part of the beam to be diverted to output port 808. The output switch 820 includes a diverting laser beam 822 which is at an angle 824 to the fiber 802. In a preferred embodiment, this angle 824 is 90 degrees, but in other embodiments, this angle may vary depending upon the size of the fiber, the curvature of the fiber, and the radiation intensity or plasma energy level within the core 802 (as well as the intensity of the diverting beam 822). Each of these factors may determine the positioning of diverting laser beam 822.

The diverting laser beam 822 effectively exerts a lateral pondermotive force or pressure on the existing plasma within the fiber, in effect causing acceleration toward the output port 808. The Lorentz force (v x B) from laser 822 causes the plasma to drift outward to the port 808.

The beam 822 can be operated intermittently, such as where the beam intensity ramps (one or more pulses) rapidly so as to effectively push a"slice"of the circulating plasma out the port beamline until the constriction collapses and the plasma is again contained within the fiber. A secondary pondermotive or magnetic field can be created in the beamline port itself to further guide the ejected plasma out the port without significant interaction with the walls of the ejection port fiber. It will be recognized, however, that the ports need not be linear as shown, and in fact may comprise simply an extension of the circular (primary) path of the core. For example, consider the case where a curved portion of fiber having a radius substantially identical to the primary fiber path is used.

It will also be recognized that other mechanism or techniques may be used to provide the output port switching function. For example, an intensified magnetic field can be created at the location of the open port in a direction and gradient such that the pondermotive forces are substantially maintained at that point of the fiber. Only when the field collapses does the port"open"such the pondermotive field is at least partially weakened in the region of the port, and a portion of the circulating plasma stream is diverted out the port. Similarly, an external magnetic field of sufficient strength can be used to deflect the path of at least the charged particles to a desired trajectory.

As yet another alternative, a"bucking"pondermotive field (such as created by a laser pulse propagating in the reverse direction) can be used to selectively destroy the pondermotive containment field at one or more locations within the fiber, thereby allowing a radial excursion of plasma and other species (such as through a circumferential"grating" formed at one or more locations in the fiber wall).

The cascade fusion ignition of the present invention is somewhat of a combination of inertial confinement, similar to cluster ignition, and laser confinement. The laser's pondermotive force both drives the plasma down the core and shapes it and confines it. It is another example of what has become known as"atom optics", or the guiding of atoms by light.

The aforementioned pondermotive force or photon pressure is due to the Lorentz force of the photon's electromagnetic field (e. g. F=qE+qVxB). At relativistic speeds, this relationship is more accurately represented as in Eqn. (8): Eqn. (8) In a real sense, the photon pressure is another example of magnetic confinement due to the qVxB term. The difference, however, is in the size of the magnetic fields. The localized photon magnetic field of the laser has been estimated by hydrogen line broadening techniques to exceed 10 MGauss. This is significantly larger than the 20-30 kGauss fields produced in a typical Tokamak. While the present invention can be adapted to larger scale architectures, small size actually aids in the creation of such intense magnetic fields, since the high power density of the incident laser (s) is coupled into and confined within a very small space. Stated simply, it is much easier to create a Mega-Gauss-level magnetic field in a small fiber volume than a larger containment such as a Tokamak torus.

Similarly, as laser power densities increase to 102° watts/cm2 and higher, the pondermotive photon forces associated with such power densities allow plasma confinement in smaller and smaller architectures including, e. g., the"recirculating" architecture of Fig. 12. These small architectures are even amenable to manufacture using integrated circuit fabrication technology. Accordingly, while the illustrated embodiments are rendered primarily in terms of"table top"or comparatively larger sized devices, it is envisaged that improvements in the extant technologies and processes over time will allow reduction of the size of the core (and entire apparatus) of the present invention to very small size, even so as to be contained within a single or hybridized"SoC"type integrated circuit package. Specifically, the holey fiber structures may be rendered at a micro scale, such as being etched in one or more layers or structures of glass, silicon, silica, diamond, carbon and other materials.

In such an integrated circuit device, the fusion apparatus may also contain its own integrated fuel source of hydrogen, deuterium, etc. For example, the Hydrogen or Deuterium fuel can be stored within the hollow fibers by diffusing the gases through the glass fiber walls at elevated temperatures (approx. 200-300 degrees C) and releasing the stored gas by using elevated temperatures again (laser activated process). Internal pressures of stored gases in silica fibers can exceed 8000 PSI. As previously discussed, certain materials (e. g. , glass such as Kodak's Vycor brand) allow water vapor to diffuse through the glass walls, thereby acting as a fuel delivery mechanism. The hydrogen (including minute deuterium and tritium concentrations) intrinsically present in water vapor can be used to provide the fuel, or alternatively the vapor can be enriched with the heavier isotopes or even other fuels (such as, e. g. , Lithium). Alternatively, the fuel can be impregnated into the walls of the minute fiber (s) (such as at high temperature), and then released into the lumen by again heating the fiber walls as previously described.

Referring now to Fig. 13, and alternative embodiment of the fusion core of the present invention is shown and generally designated 900. The fusion core 900 of this embodiment includes a fiber 902 formed with multiple radiation inlet ports 904A-H for receiving radiation 906A-H. The inlet ports 904 are mode-coupling devices for coupling radiation into the fiber 902. This radiation, once coupled into fiber 902, is circulated in a given direction 910 and reacts with fusion fuel introduced through fuel inlet ports 918 until the plasma beam 113 exits output port (s) 914.

Ejection of the plasma 913 from the fiber 902 is the result of output plasma switch 920. The output switch 920 is equipped with, e. g. , a perturbing laser 922 for introducing energy into the plasma beam to redirect the plasma 913 out exit port 914 as previously described herein with respect to Fig. 12. The output switch 920 can alternatively comprise magnetic fields which are adapted to switch the plasma out via the port (s) 914.

In the recirculating architectures of Figs. 12-13, the recirculating plasma inside the hollow fibers will have axial velocities on the order of 0.9 the speed of light, and consist mostly of light particles including electrons, protons, neutrons, positrons and the charged nuclei of light elements such as oxygen and nitrogen. The recirculating architectures, with one or more exit"portals"akin to the beamline ports of the well known synchrotron ring, can be used for any number of purposes including without limitation research or ion implantation into materials. It will also be recognized that the ejected ions, etc. carry with them momentum (p = mv), thereby inducing a reaction force according to conservation principles. Hence the present invention can be configured as an ion-propulsion engine. One application of such a technology is as an engine for space vehicles.

Similarly, plasma inside the hollow fiber (s), whether in the linear or recirculating architecture or otherwise, can also be configured to act as a plasma/ion weapon for military or other uses. Specifically, a relativistic beam of neutrons, ions, electrons, etc. would have great lethality against biological entities as well as non-living materials (e. g. , penetration of shielded warheads or other components such as tank armor, buildings, aircraft components, etc. ) It will also be appreciated that the recirculating architectures disclosed herein can be configured with one or multiple unconnected or connected loops, the latter used to increase the volume of plasma and allow a longer laser/plasma interaction path for greater extraction of laser energy. For example, it is envisaged that a helix of many turns having a radius on the order of a few centimeters can be fashioned to provide an effective fiber length of many hundreds of meters or even kilometers. Furthermore, the laser energy can be introduced at multiple points along the path of recirculation, as shown in the exemplary configuration of Fig. 13 wherein energy is inserted at two or more portals disposed along the periphery of the loop (s).

In yet another variant (Fig. 13A), the fiber coil (s) of the core can be disposed in a helical fashion (including those with variations in the radius and/or spacing between turns) or others so as to capture neutron, EMR and other energy emitted within certain solid angles, in effect"reusing"within other portions of fiber. Specifically, the neutrons/energy emitted within the interior solid angles of each fiber turn will intersect other fiber turns disposed opposite of the emitting turns, the emitted energy being absorbed by the fuel within the other turns, thereby increasing the energy in that region of the fiber. Similarly, dual or multiple concentric helices (same lay or inverse) may be used (Fig. 13B), or interlocked non-concentric helices with the same lay (Fig. 13C). The helical or coiled fiber may also comprise a plurality of bundled fibers such as shown in Figs. 9 and 10 herein, which may be in a straight, spiral or even braided geometry if desired. Myriad other geometries which provide for energy"reuse"as described herein will be appreciated by those of ordinary skill. These geometries can also be adapted to include one or more laser insertion ports and ejection ports as shown in Figs. 12 and 13.

Additionally, neutron reflective material can be added selectively outside of the helix to reflect energy inward. Individual turns of the fiber (s) can also be coated individually (whether internally or externally) if desired, such as with Beryllium, Deuterium Oxide (D2O), or 58Ni/Mo.

In yet another embodiment of the invention shown in Fig. 13D, an exemplary collider apparatus is provided. Specifically, two or more of the recirculating architectures of Figs. 12 and 13 are disposed in mirror-image to one another, with their ejection beam ports positioned to cause collisions between the plasma effluent of the ports, either directly or at an oblique angle. As can be appreciated, the collision of ejected plasma at near relativistic speeds can be used to produce certain types of elemental particles and species, or for other purposes. The collision chamber 950 of Fig. 13D can be instrumented to detect these species, as well as shield against emissions from the chamber. As shown in Fig. 13E, multiple loops can be used in a two-dimensional (e. g. , hexagonal) or even three- dimensional (e. g. , spherical or truncated icosahedron) configuration to provide increased plasma density within the chamber.

Referring to Fig. 14, a cross-section of yet another alternative embodiment of the fusion core of the present invention is shown and generally designated 1000. This fusion core 1000 includes a fiber 1002 formed with a hollow core 1004 and having an inlet seal 1006 and an output seal 1008 to define a fuel chamber 1010 within the fiber 1002 between the input seal 1006 and the output seal 1008.

A fusion fuel 1012 may be positioned within fuel chamber 1010, and may in a preferred embodiment comprise a solid fuel coated on the inside surface 1011 of hollow core 1004. A fuel vapor 1014 may also be contained within fuel chamber 1010 and retained within fuel chamber 1010 by seals 1006 and 1008. A solid fuel pellet 1016 may also be positioned on the input seal 1006, and a fusion fuel 1018 material may also be positioned on the output seal 1008. One or more of these approaches can be used as desired.

The fusion core 1000 of the present embodiment is capable of being charged with fusion fuel, and then stored or maintained for some time prior to creation of the fusion reaction. Herein lies a significant advantage over"frozen cluster"or other transient approaches. More specifically, the fiber 1002 may be charged with one or more of the fusion fuels 1012, 1014,1016, or 1018 and then sealed with input seal 1006 and output seal 1008 (and optionally evacuated of air or filled with a purge gas). Once sealed, the fusion core 1000 may be stored for a period of time for future use. Any number of sealing materials may be used, including for example glass, quartz, or polymers (such as polyethylene). Solidified fuel itself may even be used for the output seal 1008.

When a fusion reaction is desired, fusion core 1000 may be removed from storage and exposed to a radiation source, such as a laser. This radiation source enters fusion core 1000 in direction 1019 and strikes input seal 1006 which may be transparent or translucent to the incoming radiation, or it may be opaque to the incoming radiation. In the event the input seal is translucent or transparent to the incoming radiation, the radiation passes substantially through the seal 1006 and strikes the fusion fuel 1012,1014, 1016 and/or 1018 to create a fusion reaction and form a plasma beam 1020. Plasma beam 1020 strikes and obliterates output seal 1008 and exits as plasma 1022.

In circumstances where input seal 1006 is opaque to the incoming radiation, the seal 1006 is obliterated by the incoming radiation thereby allowing the radiation to strike fusion fuel 1012, 1014,1016, and/or 1018 contained within fuel chamber 1010. Radiation striking the fusion fuel creates a fusion reaction which in turn generates a plasma beam 1020 that passes through output seal 1008 as plasma 1022.

In an alternative embodiment of the fusion core, a radiation source 1026 may be provided. More specifically, radiation source 1026, such as a laser diode or other known or discovered radiation source, may be positioned at least partly within the fiber 1002. Laser diodes are well known to those of ordinary skill in the art, and accordingly are not described further herein. When a fusion reaction is desired, a power source, such as battery 128 may be attached or connected to the radiation source 1026 to generate the radiation energy necessary to initiate a fusion reaction. This embodiment of the present invention provides for a substantially self-contained fusion plasma generator. It will also be recognized that the fiber 1002 can be elongated as necessary to provide the desired level energy concentration and fusing to occur.

In that the aforementioned cores 1000 are substantially self contained (even without the laser diode or other indigenous source), they can be used much as any other self- contained expendable commodity. For example, a revolver-type rotary structure (not shown) can be used with the cores, such that after each core 1000 is expended, a new core 1000 is rotated into a"barrel"so as to be aligned with the (stationary) pumping laser source. Alternatively, the cores 1000 can be fed magazine-style through the aforementioned apparatus and ejected after they are expended (akin to a linear prior art machine-gun or rifle clip). A multi-barrel rotary structure may also be used to increase the energy output per unit time, akin to the well known Gatling gun or more modern Vulcan rotary cannon. It will be appreciated that with recent and projected advancements in femto-second laser technology as well as holey-fiber fabrication, the foregoing devices could conceivably be reduced to a rifle-size or even hand-held device, the effluent plasma, particles and EMR providing a formidable weapon or cutting tool or the like. This is particularly true where the cores 1000 are coupled with the recirculating geometry of Figs. 12 or 13, the latter allowing for increased energy density of the effluent.

In yet another embodiment, the cores 1000 can be cascaded or disposed in series such that plasma and effluent emanating from one core 1000 acts as the input to a subsequent core 1000.

Referring to Fig. 15, still another alternative embodiment of the fusion core of the present invention is shown and generally designated 1100. In this configuration, the fusion core 1100 includes a main fiber 1102 formed with a hollow core, or lumen, 1104 and having a plurality of"feeder"input fibers 1106,1108, 1110 and 1112 for receiving radiation 1114,1116, 1118 and 1120, respectively. As shown in this Figure, the first radiation 1114 has an intensity 1l, the second radiation 1116 has an intensity 12, the third radiation 1118 has an intensity 13, and the fourth radiation 1 120 has an intensity 4. Each input fiber 1106,1108, 1110, and 1112 is formed with a hollow core 1122 such that radiation 1114., 1116,1118, and 1120 enter core 1104 of fiber 1102 to form a composite radiation 1124. The composite radiation 1124 has an intensity roughly equivalent to the sum of the intensities of the constituent radiation 1114,1116, 1118, and 1120, and reacts with fusion fuel 1126 within core 1104 to create a fusion reaction and generate a plasma beam 1130. It will be appreciated that while a substantially two-dimensional configuration is shown in Fig. 15, other configurations may be used, such as where an equal or greater number of constituent fibers are disposed in radial or circumferential fashion around the periphery of the central core fiber 1012. As another alternative, a number of smaller diameter straight fibers are placed in parallel bundled disposition at the ingress of a larger diameter"collector"fiber having diameter roughly equivalent to that of the bundle.

In an alternative embodiment, additional fusion fuel 1134 may be added to core 1104 of Fig. 15 through one or more fuel ports 1132 (shown in dashed lines). Such fuel ports 1132 provide for the addition of any fusion fuel thereby further enhancing the fusion reaction within fiber 1102. This port 1132 may also be used in conjunction with the other fuel introduction mechanisms previously described herein (e. g. , ports through the fiber wall, diffusion, embedded fuels released at elevated temperature, etc. ) if desired.

Figs. 16A-D provide end-views of various alternative embodiments of optical fibers being used in the present invention. More specifically, Fig. 16A depicts a fiber designated 150 having an oval cross-section. Fig. 16B depicts a fiber designated 1160 having a round cross-section. Fig. 16C depicts a fiber designated 1170 having a square cross-section. Fig.

16D depicts a fiber designated 1180 having a triangular cross-section. While a number of specific shapes for fibers used in the present invention have been disclosed herein, these are merely exemplary of preferred embodiments, and no limitation as to the shapes of fibers used in conjunction with the present invention is contemplated herein. For example, other shapes may be proven to be optimal for certain applications, such as a rectangular (wave- guide like) shape, egg-shape (asymmetric oval),"bow tie", octagon, hexagon, pentagon, parallel-piped, etc. Furthermore, any given fiber need not be restricted to one cross- sectional configuration and/or wall thickness; it is envisaged that various applications of the present invention may utilize fibers having cross-sectional shapes and/or wall thickness that varies as a function of their length.

It will also be recognized that the hollow cores of the fibers used in the illustrated embodiments need not have constant geometries relative to size or shape. The interior walls of the fibers can include various features such as e. g. , undulations and modulations of the geometry of the fiber, also optionally in conjunction with changes in the spatial distribution and/or density (or composition of the fuel). Such variations can be used for any number of purposes, including e. g. , to induce desired X-ray, UV or other emissions (such as via acceleration of the charged particles), or longitudinal and/or radial"clumping"of the plasma to produce pulses or pulse trains of plasma or its constituent components, or alter the laser pulse velocity in a given direction. For example, charged particle clumping can be created due to the variation in field density within the fiber core as a function of longitudinal position, whereas neutrons will not be substantially affected or clumped due to a lack of charge.

In one simple embodiment, the fiber is tapered at a substantially constant rate as previously described in effect to compress and accelerate the plasma as propagation down the fiber occurs. In a second variant, the rate of taper per linear distance is varied, such that the rate of compression and acceleration is controlled. In a third variant, the thickness of the core channel is varied according to a functional relationship (e. g. , a sinusoid or saw- tooth function). In another variant, the channel diameter can conform to a substantially discrete or binary arrangement, wherein step-changes in diameter are provided, thereby creating some degree of backward reflection (in effect inducing a turbulence within the propagating wave). Heterogeneous (i. e. , mixed) tapers may also be used within the core (or even within an individual fiber) if desired in order to achieve particular objectives.

Similarly, no taper at all (or even an expanding chamber or inverse taper) can be used. This latter seemingly counter-intuitive result stems primarily from the presence of the aforementioned mode-coupling between fibers ; e. g. , where one or more fueled fibers are surrounded by other fibers, the latter coupling at least a portion of their photon and EM energy into the fueled fibers in order to increase the field intensity within the fueled fibers, even where the lumen diameter is progressively expanding as the wavefront propagates down the fiber (s).

It will also be recognized that the application of external electric or magnetic fields to the fiber can be varied as a function of longitudinal, radial, or angular position if desired.

For example, a sinusoidal magnetic flux profile can be created within the fiber core using an externally applied field in order to affect the plasma in a desired fashion, such as e. g., "pinching"the plasma or the pondermotive field.

The externally applied magnetic field may also be used to enhance acceleration of the charged particles formed within the plasma in one direction or another. For example, by creating a transverse magnetic field at the end of the fiber (i. e. , at its effluent), charged ions (+ or-) passing through the field feel an orthogonal force which drives the particles in one direction or the other (depending on their charge and the applied field vector). The ejected plasma will be broken into three distinct components: (i) positively charged particles deflected toward one direction; (ii) negatively charged particles in a substantially opposite direction, and (iii) charge-neutral particles (neutrons, photons, etc. ) along the line of initial ejection. By rotating the magnetic field vector rapidly around the longitudinal axis of the fiber (or alternatively rotating the fiber), a frustoconic section of charged particles is created, with a neutral particle jet or stream along its center axis, with the radius of the frustoconic section being related to the strength of the field and its placement relative to the effluent of the fiber.

Such separation of charged and neutral particles may be useful where the two classes of effluent are to be used for different purposes, or where only a substantially charged or un-charged plasma stream is desired. Alternatively, moving the fiber linearly relative to a transverse B-field (or vice versa) will tend to accelerate the ions along their original line oftravel (along longitudinal axis of the fiber).

Furthermore, it will be recognized that the fiber core or lumen region need not necessarily be hollow, but could feasibly be formed of a material which allows energy propagation in the longitudinal dimension of the fiber, and the establishment of the desired containment field (s). In a simple case, the core might comprise a gaseous substance having deuterium, tritium, or other fuels atomized and suspended therein. In another variant, one or more segments of solid material (such as an optically transparent polymer) may be disposed within the lumen region. Alternatively, it may be desired to evacuate the core of the fiber from any ambient air or other materials to the maximum degree practicable.

Referring now to Fig. 17, another alternative embodiment of the present invention is shown and generally designated 1200. The fusion core 1200 of this embodiment includes a fiber 1202 formed with a hollow core (not shown in this Figure) and containing a fusion fuel (also not shown). A substantial portion of fiber 1202 is positioned within a cooling chamber 1204 and bathed in a cooling fluid. This cooling fluid, such as water, flows in a first direction 1206 through a pump 1208 and through a cooler 1210 and in direction 1214 for re-introduction into the chamber 2104. It will be appreciated that a counter-flow arrangement may be used as well. In this embodiment, laser radiation 1218 enters fiber 1202, reacts with the fusion fuel therein, and exits as a plasma beam 1220. The cooling fluid circulates in the shown direction 1222, and is recirculated through pump 1208 and cooler 1210 to chill the fiber 1202 by extracting thermal energy therefrom, whether by direct contact with the fiber (conduction), via an interposed medium such as air (convection), and/or simply by absorbing radiated photons and particles (radiation).

In some circumstances, cooling of the fiber 1202 may be necessary to maintain the fiber at a safe temperature and to avoid damage to the fusion core of the present invention.

However, such cooling also transfers thermal energy to the cooling medium, which can be used for other productive purposes such as to generate steam, provide heated water. In one variant, the water or other cooling medium is used in conjunction with a recirculating core of the type shown in Figs. 12-13 herein. By continuously (or intermittently) injecting fuel into the fiber core, and pumping with laser energy, a virtually limitless source of heat energy can be exploited. In contrast the embodiment of Fig. 17, this recirculating geometry need not even have an effluent port, since the effluent is not the primary energy source of interest. Rather, the thermal/radiation heating of the fiber (and hence the cooling/heat transfer medium) is paramount.

Similarly, neutron, gamma, and thermal energy can be captured within other fluid volumes disposed proximate to the fiber core. For example, in the case of the helical fiber core geometry described with respect to Figs. 13A-13C, a central chamber disposed within the interior region of the helix can be filled with water or another substance efficient at absorbing the particle/EMR effluent from the fibers, thereby heating the substance or otherwise making use of the radiated energy. In a simple example, a tube or pipe of water can be disposed in the helix interior region, and water recirculated there through, the water being heated on each pass by incident neutron, gamma ray, and infrared radiation.

It will also be appreciated that a refrigerant (R11, R12, R114, etc. ) can be used in place of the water loop of Fig. 17 if desired. For example, cool air can be blown or otherwise interfaced with the fiber or core exterior in order to extract heat therefrom. This approach may be preferable to water where high thermal stresses may result in cracking of the fiber or core. It is envisaged, however, that even cryogenic systems could be employed consistent with the present invention, such as for example via a heat exchanger or other indirect conduction/convection mechanism.

In another exemplary embodiment of the invention, a magneto-hydrodynamic (MHD) generator is used in conjunction with the fusion apparatus previously described. An MHD generator of electricity has been likened to a magnet placed onto the exhaust of a turbojet engine. Hot plasma with fully ionized atoms is created within the engine. When the plasma passes through a transverse magnetic field, positive and negative charges are deflected in opposite directions. Collecting plates for the charges provide a DC voltage. The faster the charges can be delivered to the plates, the greater the energy and power capacity of the generator. With fusion plasmas, the charges are delivered at relativistic speeds approaching c, the speed of light, thereby advantageously delivering very significant energy per unit time.

MHD offers the possibility of very high plasma fuel utilization because of the super high temperatures at which it operates. For the fusion generator, this temperature is in the millions of degrees and correlates with a comparatively high Carnot efficiency. The process is illustrated in the Fig. 18. Unlike early experiments with MHD, the fusion plasma is a highly conductive"fluid"with a large density of free electrons and positively charged ions, and therefore is well adapted to the present application.

In the prior art, MHD generators have been utilized as energy conversion devices powered by the burning of fossil fuels like gas, oil and alcohol. Maximum working fluid temperatures were in the vicinity of 3000 degrees K. Power generation of 50 to 100 MWatts were readily produced. Due to engineering limitations, maximum Carnot efficiency was never much more than 45%. Calculations show that fossil-fueled MHD generators cannot operate at efficiencies greater than approximately 60%.

Unlike turbine generators, MHD power generators advantageously do not require the use of moving solid materials (e. g. , blades) in the plasma stream. This means they can operate at much higher temperatures, on the order of millions of degrees K. This kind of robustness and efficiency leads to improved conservation of natural resources, less rejected energy/heat pollution, less maintenance, and significantly lower fuel cost.

The exemplary MHD generator shown in Fig. 18 herein is referred to as a "continuous electrode"Faraday generator. It will be recognized, however, that other MHD designs with alternate geometries may be used consistent with the invention. For such a device, calculations show that the electrical power delivered is proportional to the square of the plasma speed times the square of the magnetic field. The plasma speed in the fusion generator of the present invention approaches the speed of light (i. e. , approaching 3X108 m/sec). Compared to the roughly 1,000 m/sec speed typical of fossil fuel plasmas ; the fusion MHD generator of the present invention can deliver nearly 1011 times more power.

This is enormous, but further increases are possible. Specifically, conventional superconducting magnets used in MHD generators can create fields of 20,000 Gauss (or 2 Tesla). The magnetic fields associated with Wakefield plasma acceleration from femto- second lasers have been measured at greater than 100 million Gauss. The ratio of magnetic fields is therefore on the order of 5xi03. This means that if the fusion plasma fields are utilized in the MHD generator, power output can be more than 1018 times greater than for fossil fuel MHD generators.

Additionally, it will be recognized that the basic principle associated with the MHD may be used to effectively"steer"the plasma ion beam at the effluent (port) of the core.

Specifically, with proper application of magnetic field (s), the trajectory of the positive and negative ions present in the plasma can be altered. Such steering may also be used to indirectly affect the trajectory or other properties of other constituents within the plasma effluent, such as where the kinetic interaction of the"steered"charged particles alters the trajectory of neutral particles (e. g. , neutrons) disposed within the effluent. Furthermore, so- called"drag"can be used to affect one type of charged particle using another; e. g. , where the applied magnetic or electric field is used to steer electrons, whose intrinsic electric field interacts with that of nearby protons in the plasma, the inter-particle field interactions causing an effect on the proton trajectory.

It will also be appreciated that the effluent plasma, particles and energy can be used to power a conventional device such as for example a steam cycle plant or engine. In one embodiment, the effluent radiation is used to heat a working fluid (such as water) to a boiling temperature at the prescribed system pressure, such heat which can then be extracted across the blades of a high or low pressure steam turbine or other such mechanism well known to those of ordinary skill.

While the foregoing variants have been described primarily in terms of a conventional (e. g. , femto-second) laser, it will be appreciated that the present invention can be practiced using other pumping sources, such as for example an X-ray or UV laser of the type well known in the physics arts. In one exemplary embodiment, the X-rays generated by the laser are coupled into the fiber core (s) of the type previously described herein, to interact with fuel resident therein. However, so-called"charged"Hafnium (such as that recovered from particle accelerator waste or hafnium control rods obtained from nuclear fission reactors) is used as a fuel. As is well known, exposing charged Hafnium to"soft" X-rays (e. g. , 90 keV) can induce a gamma ray cascade effect. As can be appreciated, there are many different uses for such a gamma source, including without limitation research, materials testing, weapons, photolithography, or sterilization against microorganisms.

It has been known for many years that the nuclei of some elements, such as Hafnium, can exist in a high-energy state (nuclear isomer) that slowly decays to a low-energy state by emitting gamma rays. For example, Hafnium-178m2, which is the excited, isomeric form of Hafnium-178, has a half-life of 31 years. The possibility that this process could be rapid in nature was discovered when Carl Collins, et al. (University of Texas at Dallas) demonstrated that the decay of the hafnium isomer could be triggered by bombarding it with low-energy or "soft"X-rays (see, e. g., New Scientist print edition, 3 July 1999; C. B. Collins, et al, Phys Rev Lett 82,695 (1999), and Collins, et al, Phys Rev 84,2544 (2000), each incorporated herein by reference in its entirety). Ostensibly, the Collins experiment released many times as much energy as was put in, and in theory greater energy releases can be achieved.

To produce such"charged"Hafnium, energy has to be pumped into its nuclei. The nuclei later return to their lowest energy states through the emission of gamma-ray photons. In one exemplary embodiment of the present invention, the charged Hf is produced by bombarding Tantalum with protons, causing it to decay into Hafnium-178m2 as is well known in the nuclear arts. This can be accomplished using a nuclear reactor or a particle accelerator. Advantageously, only small quantities of the charged Hf (e. g. , 178m2) fuel are required to fuel the gamma ray generator of the present invention. Alternatively, the charged Hf can be extracted or refined from nuclear fission reactor control rods or other comparable parts, which have been subjected to extensive irradiation to neutrons, gamma rays, charged particles, etc. created as part of the fission process. As yet another alternative, the Hafnium isomer can be created by bombarding ordinary Hafnium with high-energy photons. See also the methodologies of U. S. Patent No. 6,639, 222 to Putvinski, et al. issued October 28,2003 entitled"Device and method for extracting a constituent from a chemical mixture" incorporated herein by reference in its entirety.

It will also be recognized that since Hf-178m2 can be created by bombarding Tantalum with protons, the energetic protons (and photons) generated through operation of the of the fusion apparatus previously described herein can be used to bombard the Tantalum to produce the Hf isomer, in effect forming a"breeder reactor"of sorts. Specifically, by directing the plasma effluent (or portions thereof, such as that separated by the application of an external magnetic field at the effluent of the fiber as previously discussed) into a quantity of Tantalum, the Tantalum can be converted into the Hf isomer. The isomer can then be used to fuel the gamma ray device previously described. This process can be made as separate steps, or alternatively integrated into one device if desired.

For example, a"first stage"Deuterium-fueled fusion device can be used to bombard Tantalum fuel prior to introduction to the gamma ray device fiber lumen, the bombardment creating some percentage of Hf isomer within the Tantalum. When the partially isomer-laden fuel is irradiated with the X-ray pump, gamma rays are generated.

As yet another alternative, the process can even conceivably be conducted within a single fiber. Specifically, the Tantalum material can be placed or introduced into the fiber lumen and irradiated with one or more femto-second laser pulses, thereby generating a population of high energy protons in the lumen, which will have a finite probability of interacting with the Tantalum atoms present in the lumen. Those which do interact produce the Hf isomer (s), which can then be pumped with second (set of) pulses from the X-ray laser or other source. This second pump generates the fusion event which produces the gamma radiation in significantly increased quantities.

It will be recognized that the fuel for fusion apparatus discussed above can also be "salted"with the Hf or other isomer, and dual pump sources used. Specifically, in one embodiment, a small fraction (i. e. , a few percent) of the weight by mass of the deuterated or other fuel comprises the Hf-178m2 isomer, and the femto-second laser pulse train is punctuated by periodic (or even overlapping) pulses from the X-ray laser. Hence, when no X- ray laser pulses are present, the wavelengths of the femto-second laser are insufficient to generate an significant gamma ray production according to the mechanisms described above.

However, in the event that an increase in gamma ray output is desired (such as where the lethality of a weapon against biological targets is desired), the X-ray laser can be switched on, and/or the Hf fuel concentration increased (such as via injection by the fiber wall ports) so as to increase the gamma ray profile emitted from the fiber.

Fuel for this embodiment can also include charged nuclear spin isomers such as from materials other than Hafnium including Thorium and Niobium. It is also envisaged that the fuel can be tailored to emit a spectrum of gamma rays have one or more desired energies, thereby allowing tuning of the effluent for specific purposes. For example, it may be known that certain gamma ray energies are more lethal or penetrating than others, and hence the effluent population can be tuned using proper fuel choice, incident X-ray/UV wavelength and intensity, etc.

As with the femto-second lasers described above, all fiber arrangements, features and geometries are available for use with the X-ray sources, including without limitation, linear and recirculating architectures, bundled or stand-alone fibers, tapered or non-tapered fibers, "modulated"fibers, heterogeneous combinations of fibers, mode-coupling, etc.

Also, the apparatus described above can be used as a recycling facility for materials such as spent (charged) Hafnium or similar waste, rather than burying the same in an underground facility such as Yucca Mountain in Nevada. Specifically, the charged Hafnium is substantially consumed in the extreme environment of the fiber lumen under X-ray pumping. The de-excitation of the Hf or other isomer also releases its stored energy as gamma radiation. Furthermore, by employing a recirculating architecture, the Hf or other isomer can be repeatedly"emptied"to ensure that it is completely reduced to a ground state and passivated. The ejected gamma rays, X-rays, neutrons, plasma, etc. can be harmlessly dissipated in, e. g. , a tank of water and/or lead block, or directly into the ground at the site where the apparatus is located.

The foregoing self-contained configuration (Fig. 14) can also be advantageously used with the charged Hafnium or similar fuel, such that a repository of pre-made gamma ray "bullets"are available for subsequent use. Unlike the depleted Uranium munitions now ubiquitous, the bullets of the present invention do not produce a significant amount of activated residual, since the Hafnium is substantially eliminated during the fusion process.

Hence, the expended bullets can be stored for a brief period of time to allow any residual activity to decay, after which time they can be disposed of as is any non-activated material.

It will be recognized that while certain aspects of the invention are described in terms of a specific sequence of steps of a method, these descriptions are only illustrative of the broader methods of the invention, and may be modified as required by the particular application. Certain steps may be rendered unnecessary or optional under certain circumstances. Additionally, certain steps or functionality may be added to the disclosed embodiments, or the order of performance of two or more steps permuted. All such variations are considered to be encompassed within the invention disclosed and claimed herein.

While the above detailed description has shown, described, and pointed out novel features of the invention as applied to various embodiments, it will be understood that various omissions, substitutions, and changes in the form and details of the device or process illustrated may be made by those skilled in the art without departing from the invention. The foregoing description is of the best mode presently contemplated of carrying out the invention.

This description is in no way meant to be limiting, but rather should be taken as illustrative of the general principles of the invention. The scope of the invention should be determined with reference to the claims.