An apparatus and a method for the photolysis of a target material

Abstract

There is provided a an apparatus for the photolysis of a target material. The apparatus comprises a chamber arranged to receive a target material, at least one emitter arranged to emit an electromagnetic radiation signal at or towards the target material in use, an electromagnetic field generator configured to generate an electromagnetic field within the chamber in use, and a controller. The controller is configured to control the electromagnetic field generator to generate an electromagnetic field in the presence of the target material, such that the electromagnetic radiation signal emitted by the at least one emitter is incident upon the target material in the presence of the generated electromagnetic field.

Description

[0001] Title - An apparatus and a method for the photolysis of a target material

[0002] The present invention relates to an apparatus and a method for the photolysis of a solid target material, and more particularly to an apparatus and a method for the photolysis of a solid target material under the effect of an additionally generated electromagnetic field.

[0003] Photolysis is conventionally defined as the break-down, decomposition or separation of a target material into a reduced material and one or more byproducts due to electromagnetic waves. The mechanism is usually applied to chemical bonds using ultraviolet radiation but can be applied to nuclei using gamma radiation. The frequency of the radiation is typically selected as at, or near to, the energy of the target bond, which is determined by the wave equation.

[0004] However, in conventional apparatus and methods for photolysis of chemical or nuclear bonds, for each excitation of the bond, there is a reasonably high probability of the bond relaxing and recoiling again, rather than leading to scission of the target molecule or nuclei, or of the gamma ray missing the target nuclei altogether. Hence, typical photolysis apparatus and methods are particularly inefficient or insufficient to complete the scission of the target.

[0005] There has now been devised an improved apparatus and method for the photolysis of a target material, which overcomes or substantially mitigates disadvantages associated with the prior art.

[0006] According to a first aspect of the invention, there is provided an apparatus for the photolysis of a target material, the apparatus comprising: a chamber arranged to receive a target material; at least one emitter arranged to emit an electromagnetic radiation signal at or towards the target material in use; an electromagnetic field generator configured to generate an electromagnetic field within the chamber in use; and a controller configured to control the electromagnetic field generator to generate an electromagnetic field in the presence of the target material such that the electromagnetic radiation signal emitted by the at least one emitter is incident upon the target material in the presence of the generated electromagnetic field.

[0007] The apparatus according to the first aspect of the invention may be advantageous in that it enables a second or additional electromagnetic field to be applied through the chamber during photolysis of the target material, i.e. an electromagnetic field that is not created by the emitted electromagnetic radiation itself. The presence of the second or additional electromagnetic field, combined with the bond(s) in the target material already being excited by the emitted electromagnetic radiation means that sufficient energy is provided to increase the probability of scission of the bond(s) of the target material, rather than relaxation of those bond(s). In particular, the bond(s) is given sufficient energy from the applied electromagnetic field to force the constituents of the bond(s) in different directions, thereby increasing the probability of breaking the bond. The presence of the electromagnetic field during photolysis therefore improves the chance of bond scission in the target material relative to prior art apparatus and methods.

[0008] The chamber may be a vacuum chamber. The chamber may be maintained as a vacuum chamber using a vacuum pump. Alternatively, the chamber may be located in vacuum outside of the earth’s atmosphere.

[0009] The electromagnetic radiation signal may be an electron beam. The electron beam may be a high flux electron beam. The electron beam may have a flux of 1016- 1040photons / (s / mrad2 / mm2 / 10% bandwidth), a flux of 1016- 1036photons / (s / mrad2 / mm2 / 10% bandwidth), or a flux of 1016- 1034photons / (s / mrad2 / mm2 / 10% bandwidth), or a flux of 1 - 1000 kA / cm2.The electron beam may have a relativistic velocity, i.e. a velocity at which relativistic effects become significant, i.e. those such velocities that induce a strong magnetic field due to the short timescale for the change in the electric field by dE / dt and increased relative mass of electrons at relativistic speeds leading to more inelastic scattering. Thus, the electron beam may have sufficient energy to cause a state change of the molecule or nucleus. The electron beam may be accelerated by a particle accelerator, for example using resonant radiofrequency cavities, or by a photon beam such as produced by a laser wakefield accelerator, or a maser, a laser, or a synchrotron beam. In this embodiment, the chamber may be a vacuum chamber, such that the electrons do not react with atmospheric conditions when aimed at or towards the target material.

[0010] The electromagnetic radiation signal may be a photon beam. The photon beam may be a high flux photon beam. The photon beam may have a flux of 1016- 1040photons / (s / mrad2 / mm2 / 10% bandwidth), a flux of 1016- 1036photons / (s / mrad2 / mm2 / 10% bandwidth), or a flux of 1016- 1034photons / (s / mrad2 / mm2 / 10% bandwidth). The photon beam may have a relativistic velocity, i.e. a velocity at which relativistic effects become significant. The photon beam may have sufficient energy to cause a state change of the molecule or nucleus. The photon beam may be provided by passing an electron beam, e.g. the above-described electron beam, through an undulator, and / or by passing the electron beam through an electron beam filter or modulator, which may comprise thin sheets of germanium, silicon, or diamond, to produce Bremsstrahlung photons. The undulator may be a linear undulator. The undulator may be formed of flat magnet plates, or of curved magnet plates. The undulator may be a tapered undulator. The tapered undulator may comprise a first end at which the photon beam enters the undulator, and a second end from which the undulated beam exits the undulator. The tapered undulator may be tapered from the first end to the second end. The undulator may be a helical undulator, which may provide a circularly polarised photon beam. The photon beam may additionally pass through an optically transparent medium. This may enable parts of the chamber to remain under atmospheric conditions.

[0011] The electromagnetic radiation signal may be a combination of an electron beam and a photon beam that may be from the same source, or from different sources. Where different sources are used, the beams may be aligned by the use of lenses. Where the combination of the electron beam and the photon beam are emitted from the same source, the electron beam and the photon beam may be split, and may later be recombined, by the use of lenses and / or beam focussing or directioning devices. The electromagnetic field generator may comprise a first electrode placed in electrical contact with the target material. The electromagnetic field generator may comprise a second electrode placed in electrical contact with the chamber. The electromagnetic field generator may be configured to generate an electromagnetic field between the first and second electrodes. The electromagnetic field generator may comprise an array of electrodes configured to provide a non-uniform field.

[0012] The electromagnetic field generator may comprise a plurality of sources. The plurality of sources may comprise one or more electron beam and / or one or more photon beam. The one or more electron beam and / or the one or more photon beam may be emitted from the same emitter, or from different emitters. The electromagnetic field generator (and therefore the first and second electrodes, where the electromagnetic field generator comprises electrodes) may therefore comprise particles such as electrons at, near, or toward relativistic speeds, or any combination thereof. The one or more electron beam and / or one or the one more photon beam may comprise particles having different energies. The presence of two or more particles having different energies may cause those particles to form virtual electromagnetic fields and / or exchange virtual photons between them as they pass through the target material from different incident angles. Thus, it may be beneficial to provide a first electron beam having a first energy, and either a second electron beam or a first photon beam having a second energy that is different to the first energy of the first electron beam.

[0013] The first electrode may be positioned in, on or near to the target material. The first electrode may be positioned such that the target material is positioned within the electromagnetic field, or at least experiences the effects of the electromagnetic field, generated between the first and second electrodes, in use.

[0014] The second electrode may be placed in electrical contact with the vacuum pump. Each of the electrodes may be in fluid communication with a collector. For example, the vacuum pump may be in fluid communication with a collector. In particular, an outlet of the vacuum pump may be in fluid communication with a collector. This may enable the by-products of the photolysis process to be collected within the collectors.

[0015] The electromagnetic field may be applied, and / or the target material may be positioned, such that the target material is positioned within the electromagnetic field, or at least experiences the effects of the electromagnetic field, in use. The electromagnetic field may be a static electromagnetic field, a dynamic electromagnetic field, or a pulsed power electromagnetic field that may cause current to pass adjacent to, or through, the solid target material. The electromagnetic field may be a constant field. Alternatively, the electromagnetic field may be varied, for example as a sinusoidal, triangular or sawtooth wave, which may have a frequency in the range of 1 MHz to 10 PHz, and preferably in the range of 1 MHz to 10GHz. Preferably, the field is a pulsed power field. The amplitude of the pulsed field may be aligned or synchronised with the timing of pulses of the electromagnetic radiation signal emitted by the at least one emitter.

[0016] The electromagnetic field may be continuously alternating or may be continuously constant. In use, i.e. upon application of a differential electrical charge between the first and second electrodes, the first electrode may have either a negative charge or a positive charge, and the second electrode may have the other of a negative charge and a positive charge. Hence, in use, the electric field component of the generated electromagnetic field is a vector that acts away from one electrode and towards the other electrode, i.e. electric field lines may traverse from one electrode to the other electrode. This may be advantageous in that the electric field vector imparts force oppositely on the negatively charged electrons and the positively charged parent atom or nucleus, thus increasing their spatial distribution relative to the parent molecule(s) due to the bond state change in the target material. The negatively charged electrons will therefore be accelerated by the electric field towards the positive electrode, and the positively charged parent atom or nucleus may be accelerated by the electric field towards the negative electrode, where they may form a deposited layer and be collected. The electric field strength may be dependent on the excited bond length of the molecules present in the target material. The electric field may have a field strength of 10 kV / m - 1 TV / m, or preferably of 100kV / m - 1TV / m. The electric field may have a field strength of 100 kV / m - 100 GV / m. The electric field may have a field strength of 10 MV / m - 50 GV / m. The electric field may have a field strength distribution that is asymmetric. The electric field may be enhanced by the relative geometry of the first and second electrodes. Preferably, the electric field is enhanced such that very high electric fields are generated on or near the target material. This may achieve a similar effect as that caused by pin-and-plate geometries, perpendicular or parallel wire-and-tube geometries, coaxial geometries, or the field produced by the proximity of a free electron. The electromagnetic field generator may be a relativistic electron produced by a plasma wakefield. The plasma wakefield may be provided by the at least one electromagnetic radiation emitter, where the at least one electromagnetic radiation emitter is a laser wakefield accelerator.

[0017] The at least one electromagnetic radiation emitter may comprise a plurality of emitters. For example, the at least one emitter may comprise 2-100 emitters, 3-42 emitters, or 4-12 emitters. The plurality of emitters may be an array of emitters. The array of emitters may be a radial array of emitters focussed on a centre point. The array of emitters may be arranged about the circumference of the chamber. The array of emitters may be arranged equidistantly or inequidistantly about the circumference of the chamber.

[0018] The apparatus may further comprise at least one lens. The at least one lens may be arranged to focus the electromagnetic radiation signal emitted from each of the at least one emitter. The at least one lens may be arranged to focus the electromagnetic radiation signal emitted from each of the at least one emitter on or towards the target material, or where an undulator is present, on or towards the undulator. The at least one lens may be an electromagnetic lens for focussing electron beams, such as a focussing quadrupole, or a plasma lens. The at least one lens may be a dipole magnet, or arrangement of multiple dipole magnets. The at least one lens may comprise a plurality of lenses. The plurality of lenses may comprise a single lens for each of the at least one emitter. Alternatively, the plurality of lenses may be positioned between one of, or each of, the emitters and the target material. For example, the at least one lens may be configured to split an emitted electron beam into a photon beam and an output electron beam. The photon beam and the output electron beam may both be directed or focused towards the target material, for example by the at least one lens, or by at least one further lens. The photon beam and the output electron beam may both be directed or focused towards the target material such that the photon beam and the output electron beam are incident upon the target material at or from different angles. The output electron beam may additionally pass through an electric field that modifies the final velocity of the electrons hitting the target.

[0019] The apparatus may further comprise at least one temperature control mechanism arranged to cool or heat the at least one lens. The at least one temperature control mechanism may comprise a plurality of temperature control mechanisms. The plurality of temperature control mechanisms may comprise a single temperature control mechanism for each of the at least one lenses. The at least one temperature control mechanism may be a fan or liquid pump, or a thermal emission material, for example.

[0020] Each of the at least one lenses may be movable. Each of the at least one lenses may be movable to change the direction of focus of the at least one electromagnetic radiation signal. Movement of the at least one lens may be controlled by at least one control motor. The apparatus may comprise a plurality of control motors. The plurality of control motors may comprise a single control motor for each of the at least one lenses.

[0021] Alternatively, the target material may be movable within the chamber so that portions of the target may be brought into focus of the electromagnetic radiation signal. For example, a portion of the chamber may be movable relative to the at least one emitter. The portion of the chamber that is movable may be the portion arranged to receive the target material. Where the at least one emitter comprises a plurality of emitters, the portion of the chamber may be movable relative to each of the plurality of emitters.

[0022] The at least one lens or the portion of the chamber being movable may be advantageous in that it enables either the direction of the electromagnetic radiation signal to be changed relative to the target material, or the target material to move relative to the electromagnetic radiation signal. This enables the electromagnetic radiation signal to be incident on a greater portion of the surface area of the target material.

[0023] The at least one emitter may comprise a particle accelerator. The particle accelerator may comprise a linear particle accelerator, a cyclotron, a synchrotron, a maser, a laser, or a laser wakefield accelerator. The laser wakefield accelerator may be part of a synchrotron. The particle accelerator may further comprise, or be used with, an undulator. For example, the laser wakefield accelerator may be used with an undulator to form a synchrotron. This may produce photons from an electron beam. Most preferably, where the electromagnetic radiation signal is an electron beam, the at least one emitter is a maser or a laser wakefield accelerator, depending on the bubble size required for the plasma. Most preferably, where the electromagnetic radiation signal is a photon beam, the at least one emitter is synchrotron emitting. The synchrotron may comprise a maser or laser wakefield accelerator, or more specifically a maser or laser plasma wakefield accelerator. The maser or laser plasma wakefield accelerator may be provided in combination with an undulator to produce synchrotron radiation. The synchrotron may comprise a carbon dioxide laser pumped laser wakefield accelerator with an undulator, or a water maser pumped maser wakefield accelerator with an undulator. The undulator may be a single circular undulator such that radial electron beams from an array of masers or laser wakefield accelerators focus to the center of the circular undulator where the target is most advantageously located to receive the electromagnetic photon beam. The undulator may be a single undulator or an array of undulators with masers or laser wakefield accelerators sending electron beams through each undulator to form photon beams. The array of undulators may be interspaced with masers or laser wakefield accelerators that do not pass their electron beams through the undulators such that both electron beam(s) and photon beam(s) are focussed on the target material. The undulators may be tapered toward the target material. The array of undulators and masers or laser wakefield accelerators may be positioned radially such that a target material is positioned advantageously at the center.

[0024] Where the at least one emitter is a maser or a laser, the apparatus may further comprise a rail gap positioned between the at least one emitter and the solid target material. In this arrangement, the apparatus may further comprise an undulator, as described above, and the undulator may be positioned between the rail gap and the solid target material. Where the at least one emitter comprises a plurality of emitters, the apparatus may comprise a plurality of rail gaps, i.e. a rail gap positioned between each of the emitters and the target material. Similarly, the apparatus may comprise a plurality of undulators, i.e. an undulator positioned between each of the rail gaps and the target material.

[0025] Hence, according to a further aspect of the invention, there is provided an apparatus for the photolysis of a target material, the apparatus comprising: a chamber arranged to receive a target material; and at least one emitter arranged to emit an electromagnetic radiation signal at or towards the target material in use, the at least one emitter comprising at least one synchrotron source, e.g. at least one maser or laser wakefield accelerator.

[0026] This is facilitated by the recent developments to particle accelerators, and in particular to laser plasma wakefield accelerators, and their reduction in both size and cost. This may be advantageous in that the frequency of the electromagnetic radiation signal emitted by a particle accelerator, in particular when combined with an undulator, can be tuned dependent on the frequency required to excite the electrons or nucleons of the target material. In contrast, emitters such as masers and lasers have fixed frequencies, which are dependent on emission spectrum of the gas used therein. Particle accelerators and synchrotrons are therefore more adaptable for multiple target materials. The at least one electromagnetic radiation signal may have a frequency in the range of 20x109-3x1021Hz. The at least one electromagnetic radiation signal may have a wavelength in the range of 1 picometers to 1000 micrometers. The at least one electromagnetic radiation signal may have an energy in the range of 1 eV to 100 GeV. The at least one electromagnetic radiation signal may comprise gamma rays. This may be advantageous in other applications, for example in inducing scission of atoms in radioactive materials, e.g. spent uranium rods, and thereby accelerating their decay time and reigniting the nuclear process for the generation of power.

[0027] According to a further aspect of the invention there is provided a method for the photolysis of a target material, the method comprising the steps of: (a) positioning a target material in a chamber; (b) generating an electromagnetic field within the chamber in the presence of the solid target material; (c) emitting an electromagnetic radiation signal at or towards the target material in the presence of the generated electromagnetic field to induce photolysis.

[0028] The target material may be a solid material. By solid material, it is meant that the material is a solid according to the fundamental states of matter. For example, the solid target material may be nuclear waste. Alternatively, the solid target material may be plastic waste.

[0029] The method may result in the target material being reduced to a reduced material and at least one by-product. The target material may be a plastic material. The reduced material may comprise at least graphene or graphene oxide. The at least one by-product may comprise at least hydrogen. Alternatively, the target material may comprise bauxite or another naturally occurring ore. The reduced material may comprise at least carbon, graphene, aluminium, iron, silicone, titanium, or oxides or alloys thereof. The at least one by-product may comprise at least hydrogen, or oxygen, or water.

[0030] Alternatively, the target material may be nuclear waste, including plutonium, uranium, technetium, radium, iodine, potassium, thorium, actinium, tin, or the breakdown products from nuclear fuel or isotopes thereof. The reduced material may be transition elements such as radium, radon, tin, lead or isotopes thereof, or any element or isotope below the atomic weight of the target material. The byproducts may be any of, or any combination of, photons, electrons, neutrinos, protons, neutrons, alphas, and any lighter elements derived from the nuclear decay chain.

[0031] The method may comprise emitting at least one electromagnetic radiation signal that has one or more characteristic that is dependent on the bond energies within the target material.

[0032] The method may further comprise a step of moving at least one lens to change the direction of focus of the electromagnetic radiation signal emitted from each of the at least one emitter.

[0033] Alternatively, the method may further comprise a step of moving, e.g. rotating, the target material within the chamber, for example by moving, e.g. rotating, a portion of the chamber relative to the at least one emitter.

[0034] The method may comprise a step of calculating the electromagnetic field strength dependent on the excited bond length of the molecules present in the target material.

[0035] Emitting an electromagnetic radiation signal may comprise emitting a plurality of electromagnetic radiation signals. Emitting an electromagnetic radiation signal may comprise emitting a combination of different electromagnetic radiation signals. The electromagnetic radiation signals may be different in respect of their form (e.g. an electron beam or a photon beam), their fluxes, or their frequencies.

[0036] According to a further aspect of the invention there is provided a method for the photolysis of a target material, the method comprising the steps of: (a) positioning a target material in a chamber; and (b) emitting an electromagnetic radiation signal at or towards the target material; the at least one emitter comprising a maser or a laser wakefield accelerator. The maser or laser wakefield accelerator may be used with an undulator to form a synchrotron, t least one synchrotron.

[0037] According to a further aspect of the invention there is provided an apparatus for the photolysis of a target material, the apparatus comprising at least one processor configured to perform the above-described method steps.

[0038] According to a further aspect of the invention there is provided a data carrier or data storage medium comprising machine readable instructions for the control of one or more processor to perform the above-described method steps.

[0039] According to further aspects of the invention there is provided one or more processors comprising machine readable instructions for performing or controlling any, any combination of, or all of the aforementioned method steps. According to further aspects of the invention there is provided a data carrier or data storage medium comprising machine readable instructions for controlling one or more processor to perform said step(s).

[0040] Practicable embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings, of which:

[0041] Figure 1 is a cross-sectional plan view through an apparatus according to an embodiment of the invention;

[0042] Figure 2 is a cross-sectional plan view through an apparatus according to an embodiment of the invention;

[0043] Figure 3 is a cross-sectional side view through an apparatus according to an embodiment of the invention;

[0044] Figure 4 is a cross-sectional side view through an apparatus according to an embodiment of the invention; Figure 5 is a cross-sectional side view through an apparatus according to an embodiment of the invention;

[0045] Figure 6 is a cross-sectional side view through an apparatus according to an embodiment of the invention;

[0046] Figure 7 is a cross-sectional side view through an apparatus according to an embodiment of the invention; and

[0047] Figure 8 is a flowchart illustrating a method of separating hydrogen from a target material according to an embodiment of the invention.

[0048] Figure 1 illustrates a plan-viewed cross-section of an apparatus 10 for photolysis. The apparatus 10 comprises a vacuum chamber 30 having a plurality of emitters 20 that are arranged radially about a target material 50. The plurality of emitters 20 are equally spaced about the circumference of the vacuum chamber 30.

[0049] Each of the emitters 20 is arranged to emit a beam (not illustrated) towards the target material 50 placed within the vacuum chamber 30 in use. Between the emitters 20 and the vacuum chamber 30 is a circular undulator 60, arranged to focus and accelerate the emitted beams towards the target material 50.

[0050] An electrode 40 is positioned to be in electrical contact with the target material 50 in use. The electrode 40 may be movable so that it can be placed in or on the target material 50 itself, or in the chamber 30 in a position that receives the target material 50 in use.

[0051] Figure 2 illustrates an alternative plan-viewed cross-section of an apparatus 110 for photolysis from above. The apparatus 110 comprises a vacuum chamber 130 having a plurality of emitters 120 each arranged in their own individual tube radially about a target material 150. An electrode 140 is positioned to be in electrical contact with the target material 150 in use. Each individual tube, and hence each emitter 120, comprises a tapered undulator 160, arranged to focus and accelerate the emitted beams towards the target material 150.

[0052] Figure 3 illustrates a cross-section of an apparatus 210 for photolysis from the side. The apparatus 210 comprises a vacuum chamber 230 having a plurality of emitters 200, of which only one is shown due to the view. The emitter 220 shown in Figure 3 is a laser wakefield accelerator (LWFA). The circular portion of the LWFAs is not shown in Figure 3, but in this embodiment, charged particles are accelerated through a sequence of magnets arranged in a loop, until they reach almost the speed of light, at which stage they produce a beam 270, which is directed through the vacuum chamber 30 as indicated in Figure 3. Effectively, in this embodiment, the emitter 220 shown in Figure 3 represents the outlet of the LWFA.

[0053] The LWFA is arranged to emit an electron and / or photon beam 270 towards the target material 250 (again positioned in electrical contact with electrode 240), via undulator 260. The undulator 260 is arranged to focus and accelerate the emitted beam 270 towards the target material 250, forming a focused and accelerated beam 280. The arrangement may further include an optically transparent medium (not illustrated) between the outlet of the LWFA 220 and the undulator 260.

[0054] Figure 4 illustrates a side-viewed cross-section of an apparatus 310 for photolysis. The apparatus 310 comprises a vacuum chamber 330 having a plurality of emitters 320, of which only one is shown due to the view. The emitter 320 of Figure 4 is a maser or laser. The maser or laser 320 is arranged to emit an electron and / or photon beam 370 towards the target material 350 (again positioned in electrical contact with electrode 340), via undulator 360. The undulator 360 is arranged to focus and accelerate the emitted beam 370 towards the target material 350, forming a focused and accelerated beam 380.

[0055] Positioned between the maser or laser 320 and the undulator 360 is rail gap 385 comprising two rails, through which the beam emitted from maser or laser 320 passes. The rail gap may be a switch for a pulsed power system, such that the electrons in the beam emitted from maser or laser 320 are accelerated to relativistic speeds across the rail gap during the switching process. In this case, the rise time of the pulsed power discharge across the switch should be to the order of nanoseconds, or hundreds of picoseconds, to achieve multiple arcs 390, i.e. to create multiple points of electrical connection across the switch for the maser or laser beam to pass through, such that a maximum portion of electrons passing through the switch is accelerated by the beam. The maser or laser pulses may be timed to synchronise with the peak current of the pulsed power discharge across the switch. Alternatively, the rail gap current arcs may be flattened with a magnetic field acting perpendicularly to the flow of current or arc vector, such that the shape of the arcs are flattened, such that the maser or laser pulses, that are perpendicular to both the arc vector and the magnetic field vector, have more contact with electrons crossing the rail gap.

[0056] Figure 5 illustrates a side-viewed cross-section of an apparatus 410 for photolysis. The apparatus 410 comprises a vacuum chamber 430 having a plurality of emitters 420, of which only one is shown due to the view. The emitter 420 of Figure 5 is a laser. The laser 420 is arranged to emit an electron and / or photon beam 470 towards the target material 450 (again positioned in electrical contact with electrode 440), via undulator 460. The undulator 460 is arranged to focus and accelerate the emitted beam 470 towards the target material 450, forming a focused and accelerated beam 480. Positioned between the laser 420 and the undulator 460 is a magnet 497 arranged to provide additional focusing and / or flattening of the electron arc 490 emitted from the spark gap 485, 495. The magnet 497 is positioned between two spark gap electrodes 485, 495, and causes arc discharge 490 to flatten, thereby increasing the cross-section of electrons in the path of the beam 470 that enters the undulator 460.

[0057] Figure 6 illustrates a side-viewed cross-section of an apparatus 510 for photolysis. The apparatus 510 comprises a vacuum chamber 530 having a plurality of emitters 520, of which only one is shown due to the view. The emitter 520 of Figure 6 is a maser or LWFA. The maser or LWFA 520 is arranged to emit an electron and photon beam 570 towards the target material 550 (again positioned in electrical contact with electrode 540), via undulator 560. The undulator 560 is arranged to focus and accelerate the emitted beam 570 towards the target material 550.

[0058] Positioned sequentially between the undulator 560 and the target material 550 is a first electromagnetic lens 585, a second electromagnetic lens 590 and an electron accelerator 595. The first electromagnetic lens 585 splits the beam exiting undulator 560 into electrons and photons, refracting the electrons towards the second electromagnetic lens 590, which bends those electrons through the electron accelerator 595, forming electron beam 597 which is emitted towards the target material 550. The photons of the beam exiting undulator 560 are not refracted by the first electromagnetic lens 585, continuing on their path towards the target material 550 as photon beam 580. The combination of the photon beam 580 and the electron beam 597 at different angles increases the shear force on the target material 550 at the focal point, which increases the probability of reducing the target material 550 permanently.

[0059] Figure 7 illustrates a side-viewed cross-section of an apparatus 610 for photolysis. The apparatus 610 comprises a vacuum chamber 630 having a plurality of emitter pairs 620, 625, of which only one pair is shown due to the view. The emitters 620, 625 of Figure 7 are masers or LWFAs. The first maser or LWFA 620 is arranged to emit an electron and / or photon beam 670 towards the target material 650 (again positioned in electrical contact with electrode 640), via a tapered undulator 660. The tapered undulator 660 is arranged to focus and accelerate the emitted electron and / or photon beam 670 towards the target material 650, forming a focused and accelerated beam 680. The use of a tapered undulator, in particular, is beneficial in that it compensates for electron energy loss, reduces spectral sideband contamination, and produces intense and / or ultra short pulses due to the tapering effect of electromagnetic waves.

[0060] The second maser or LWFA 625 is arranged to emit an electron and / or photon beam 675 towards the target material 650 without passing through an undulator, such that relativistic electrons in beam 675 may pass virtual photons between themselves and electrons in the accelerated beam 680. The virtual photons have a larger cross section than the electrons themselves, and are at a higher energy due to relativistic effects, and therefore increase the probability of photonuclear reactions within the target material 650. The focused and accelerated beam 680 and electron and / or photon beam 675 converge at the target material 650, providing both a longitudinal converging and diverging force due to the angle between the beams at and near the focal point, leading to a shear force on the target, and virtual high energy photons between the electron beams that further convolves with the incident photon beam to cause further but broader sheer forces on the target material 650, again increasing the probability of reducing the target material 650.

[0061] The target material in each of the above-described embodiments may be movable within the chamber. This may be achieved, for example, by including a movable plate (not illustrated) on which the target material is positioned in use. In said example, the electrode may be positioned on said plate, so that it makes electrical contact with the target material when the target material is positioned on the plate. By moving the target material within the chamber, the emitted beams are able to target a greater surface area of the target material. Alternatively, this might be achieved by changing the focus of various lenses, so that the direction of the beams is varied across different portions of the target material.

[0062] Each of the apparatus described above may further comprises a second electrode (not illustrated), which is collectively arranged with the above-described electrode (herein referred to as the first electrode) such that an electromagnetic field can be applied across the chamber in use of the apparatus, i.e. such that the target material is positioned within the electromagnetic field, or at least experiences the effects of the electromagnetic field, in use.

[0063] In some embodiments, the second electrode is positioned to be in electrical contact with a vacuum pump. In use, this enables the atoms that have been separated from the target material to be transported to the vacuum pump as a result of the electromagnetic field. The vacuum pump is arranged to extract those atoms from the vacuum chamber, either during or after the photolysis operation. A collector (also not illustrated) may therefore also be present at an outlet of the vacuum pump, for collecting the extracted atoms. A conventional vacuum pump and collector may be used.

[0064] The skilled person would appreciate that the above-described embodiments represent a number of ways of focusing emitted beams in the desired direction and at the desired speed and intensity. In this respect, it will also be appreciated that the various focusing and / or accelerating arrangements of each embodiment may be combined in any way, dependent on the requirements of any given system, e.g. the directional requirements or spatial requirements of the arrangement, or the specific energy requirements of the target material.

[0065] Figure 8 illustrates a method of photolysis of a target material, using any of, or any combination of, the apparatus described in relation to Figures 1 -7.

[0066] At step 700, a target material is placed into a chamber, and the chamber is sealed to create a vacuum around the target material.

[0067] At step 710, an electromagnetic field is applied between the first electrode positioned in electrical contact with the target material, and the second electrode, which is preferably placed in electrical contact with a vacuum pump of the vacuum chamber, such that an electromagnetic field is applied in proximity of the target material, i.e. such that the target material experiences the force of the electromagnetic field.

[0068] At step 720, beams are emitted by the one or more emitters of the apparatus, and are focussed towards the target material 50. Steps 710 and 720 are typically carried out simultaneously, or at least substantially simultaneously, since the one or more beams reach the target material so quickly. When the beams interact with the target material, the photons and / or electrons within the beams excite the chemical or nuclear bonds within the target material, depending on the frequency of the beam and the target bond or energy level. This excitation can lead to a brief and temporary state change of the bond(s), increasing the energy and spatial distribution of one or more electrons relative to the rest state of the molecule, or increasing the nucleon energy to a higher state.

[0069] After the brief state change of a chemical bond, either (a) the valence electrons relax, and the bond returns to its ground state, or (b) the valence electron destabilises the molecule, breaking the molecule bond, thus reducing the target material to a reduced material, with the valence electron contributing to other byproducts.

[0070] After the brief state change of a nuclear bond or nucleon energies, the nucleons will either (a) relax, and return to the ground state, (b) become unstable and transmutate to a daughter or parent isotope due to electron capture or emission, or (c) become highly unstable and transmutate with single particle emission or undergo fission or emission of more than one particle.

[0071] In prior art arrangements, within femtoseconds, the valence electron or nucleus would typically relax again, thereby restoring (and recoiling) the relevant bonds.

[0072] However, in the above-described arrangement, because of the presence of the electromagnetic field, and the electrical charge of the valence electron and nucleus, the electromagnetic field imparts a force that is large enough to prevent this relaxation, instead providing further energy, breaking the bond and preventing reformation.

[0073] At step 730, a by-product, such as a proton, or hydrogen (where the target material is plastic), is therefore split from the molecules of the target material, as a result of the combined steps 710 and 720 described above. In this specific example, the electromagnetic field strength required to effectively break the bond between the by-product and their respective molecules can be calculated from the excited hydrogen-carbon bond length.

[0074] At step 740, as a result of the electromagnetic field, the by-product continues to be accelerated away from their previous molecules (and the target material as a whole), towards the second electrode at the vacuum pump of the vacuum chamber. At step 750, the by-product will collect and combine at the second electrode, which in the example of hydrogen atoms being split from a plastic material, forms an electromagnetically neutral hydrogen gas.

[0075] At step 760, the hydrogen gas is pumped out of the chamber by the vacuum pump typically into a collector (not illustrated in Figures 1 -7 for simplicity), so that the hydrogen gas (or any other gaseous product formed, such as short chain hydrocarbons) can be used or released appropriately. Left inside the chamber is the remains of the plastic material, which in this example is graphene.

[0076] The skilled person would appreciate that this method is also applicable to other target materials, which may lead to an alternative end product within the vacuum chamber, and / or an alternative by-product forming at the second electrode. For example, it is envisaged that both hydrogen and oxygen could be split from bauxite (and other target materials) to form aluminium, iron, silicone, titanium, or alloys or oxides thereof.

[0077] In one specific example, the target bond may be a carbon-hydrogen bond, and the excited bond is weakened and ideally temporarily broken by absorbing an electromagnetic radiation signal of around 100nm to 400nm, most preferably around 300nm, before being fully broken by the applied electromagnetic field. As a result, the hydrogen is liberated and deposited on the negative electrode due to propagation along the electromagnetic field path between the electrodes. Due to the charge-mass imbalance of the hydrogen and its valence electron, the pair may have a net velocity due to the heavier proton being slower to respond to a timevarying electromagnetic field than the valence electron, causing a net force on the pair. As such, a saw-tooth electromagnetic field path may induce a velocity on a neutral hydrogen atom that is liberated from the target.

[0078] The remaining carbon from the original bond may form new bonds with adjacent carbon atoms, as although the dissociation energy for a carbon-carbon bond is lower than the carbon-hydrogen bond, the energy is vibrational and mainly constrained to the axis of the carbon-hydrogen bond, and does not readily distribute to the adjacent bonds.

[0079] The electromagnetic field can contribute to the selection of bond by causing a polarisation of the bonds within the target material such that the target bonds are aligned with the electromagnetic radiation signal. In this way the carbon-hydrogen bond in plastics may be targeted and broken to form two separate products of mainly hydrogen and mainly carbon.

[0080] In a second specific example, the target bond may be the strong nuclear force between nucleons, or the energy state of a nucleus as a whole. In this case, gamma rays in excess of 8MeV, or on the order of picometers to nanometers are selected as the electromagnetic radiation signal. These gamma rays supply energy to the system and raise the energy state, which although not affecting the strong or weak nuclear force directly, may increase the separation of the nucleons due to some absorption of the electromagnetic force of the emitted electromagnetic signal, thus slightly weakening the binding nuclear force or bond between them.

[0081] At this time, the applied electromagnetic field (which may be a free electron in proximity to the nucleus, and could also be at a relativistic speed, or may be a virtual photon exchanged between two fast electrons travelling at near and / or toward relativistic speeds) further disrupts the stability of the nucleus by energy transfer to the nucleons that can cause the nuclear bonds to break. Magnetic alignment caused by the intense magnetic field produced by the very short time the electron charge takes to move past the nucleons, will also cause a force on the nucleons that may contribute sufficiently to break the nuclear bonds. Alternatively, a proton within the nucleus may capture the non-relativistic (and free) electron, that then becomes a neutron, and destabilises the nucleus, leading to fission due to the increased weight to charge ratio of the new isotope. In this case, the fission of the nuclei may contribute to the fission of other local nuclei, due to this neutron emission whereby the process as a whole is used to reignite nuclear waste such that it is once again in a state of useful energy generation for use in a nuclear power plant. These examples are just some of the envisaged reactions, due to the extreme variation of isotopes within nuclear waste.

[0082] In both of the above examples, the frequency of the photon beam may be accurately controlled by the use of synchrotron radiation.

[0083] It will also be appreciated that the second electrode could be positioned differently, as long as the electromagnetic field is applied in proximity of the target material and forces the relevant particles away from the target material. This may be particularly true if, for example, there is no desire to collect the by-product(s) released by photolysis of the target material, because there is no need to accelerate the particles towards an extraction pump.

Claims

Claims1 . An apparatus for the photolysis of a solid target material, the apparatus comprising: a chamber arranged to receive a solid target material; at least one emitter arranged to emit an electromagnetic radiation signal at or towards the solid target material in use; an electric field generator configured to generate an electromagnetic field within the chamber in use; and a controller configured to control the electromagnetic field generator to generate an electromagnetic field in the presence of the solid target material such that the electromagnetic radiation signal emitted by the at least one emitter is incident upon the solid target material in the presence of the generated electromagnetic field.

2. An apparatus according to Claim 1 , wherein the chamber is maintained as a vacuum chamber.

3. An apparatus according to Claim 2, wherein the chamber is maintained as a vacuum chamber using a vacuum pump.

4. An apparatus according to Claim 3, wherein the vacuum pump is in fluid communication with a collector.

5. An apparatus according to any preceding claim, wherein the electromagnetic field generator comprises a first electrode positioned to be in electrical contact with the solid target material in use.

6. An apparatus according to any preceding claim, wherein the electromagnetic field generator comprises a second electrode placed in electrical contact with the chamber.

7. An apparatus according to any preceding claim, wherein in use, the first electrode has either a relative negative charge or a relative positive charge, and the second electrode has the other of a relative negative charge and a relative positive charge.

8. An apparatus according to any preceding claim, wherein the electromagnetic field generator is configured to generate an electromagnetic field having an electric field strength that is targeted on the excited bonds present in the solid target material.

9. An apparatus according to any preceding claim, wherein the electromagnetic field generator comprises two or more particles at, near, or toward relativistic speeds, or any combination thereof, at least two of the two or more particles having different energies.

10. An apparatus according to any preceding claim, wherein the at least one emitter comprises a plurality of emitters.11 . An apparatus according to Claim 9, wherein the plurality of emitters is a radial array of emitters.

12. An apparatus according to Claim 9 or Claim 10, wherein the plurality of emitters is arranged about the circumference of the chamber.

13. An apparatus according to any preceding claim, wherein the apparatus further comprises at least one lens arranged to focus the electromagnetic radiation signal on or towards the target material.

14. An apparatus according to any preceding claim, wherein the apparatus further comprises at least one lens arranged to split the electromagnetic radiation signal into two or more output beams.

15. An apparatus according to Claim 14, wherein the apparatus further comprises at least one further lens arranged to focus the two or more output beams on or towards the solid target material.

16. An apparatus according to Claim 15, wherein the at least one further lens is arranged to focus the two or more output beams on or towards the solid target material such that each of the two or more output beams is incident upon the solid target material at or from a different angle.

17. An apparatus according to any of Claims 1 -16, wherein the chamber comprises a portion arranged to receive the solid target material, and that portion of the chamber is movable relative to the at least one emitter.

18. An apparatus according to any of Claims 1 -17, further comprising an undulator positioned between each of the at least one emitters and the solid target material.

19. An apparatus according to any preceding claim, wherein the at least one emitter comprises a particle accelerator.

20. An apparatus according to Claim 19, wherein the particle accelerator comprises a synchrotron source.21 .An apparatus according to any preceding claim, wherein the at least one emitter is a maser or a laser, and the apparatus further comprises a rail gap positioned between the at least one emitter and the solid target material.

22. A method for the photolysis of a target material, the method comprising the steps of:(a) positioning a solid target material in a chamber;(b) generating an electromagnetic field within the chamber in the presence of the solid target material; and(c) emitting an electromagnetic radiation signal at or towards the solid target material in the presence of the generated electromagnetic field to induce photolysis.

23. A method according to Claim 22, wherein the solid target material is reduced to a reduced material and at least one by-product.

24. A method according to Claim 23, wherein the solid target material is a plastic material, and / or the reduced material comprises at least carbon and forms of carbon such as graphene, and / or the at least one by-product comprises at least hydrogen.

25. A method according to Claim 23, wherein the solid target material is bauxite or another naturally occurring ore, and / or the reduced material comprises carbon, aluminium, iron, silicone, titanium, or oxides or alloys thereof, and / or the at least one by-product comprises hydrogen, oxygen, or water.

26. A method according to Claim 23, wherein the solid target material is a radioactive material such as plutonium, uranium, thorium, potassium, or isotopes thereof, or nuclear fuel waste and / or by-products, and / or the reduced material comprises any of the elements or isotopes of the solid target material, and / or the at least one by-product comprises photons, electrons, neutrinos, protons, neutrons, alphas, or any combination thereof.

27. An apparatus for the photolysis of a target material, the apparatus comprising: a chamber arranged to receive a solid target material; and at least one emitter arranged to emit an electromagnetic radiation signal at or towards the target material in use, the at least one emitter comprising at least one maser or laser wakefield accelerator.

28. An apparatus according to Claim 27, wherein the maser or laser wakefield accelerator is used with an undulator to form a synchrotron.

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