Multi-layered fusion fuel target

Abstract

To provide a fusion fuel target device for inertial confinement fusion (ICF) capable of ignition and thermonuclear burn from a laser fusion system that maximizes fusion gain while mitigating neutron emission.SOLUTION: A fusion fuel device is configured such that a first fuel material region is sandwiched between a second fuel material region in a center region and a third material fuel region in an outside region. The second fuel material region and the third fuel material region have a higher ignition temperature than the first fuel material region.SELECTED DRAWING: Figure 1

Description

Background Art

[0001] Since ancient times, humans have developed energy sources from natural substances such as wood, coal, oil, and gas products. Unfortunately, the combustion of wood and coal involves adding undesirable carbon particles to the atmosphere, leading to major pollution problems. Similar limitations exist for oil and gas products, which are the main causes of "global warming". Renewable energies including nuclear power, wind power, hydropower, and solar power are promising. However, such renewable energies have other drawbacks. Wind power can only be used when the wind is blowing. The sun cannot be used when the sun sets. Hydropower is limited to areas with water, and nuclear power, although promising, has major problems such as waste generation and unreliable and dangerous reactors. One of the other promising energy sources is fusion energy.

[0002] Fusion energy is a type of energy generation that occurs when two atomic nuclei fuse and a large amount of energy is released during the process. The fuel for the fusion reaction (mainly hydrogen) is abundant on Earth, and no greenhouse gases or other harmful pollutants are generated by the reaction, so it is considered a potential source of clean and abundant energy.

[0003] To achieve a fusion reaction, there are two main approaches: inertial confinement fusion (ICF) and magnetic confinement fusion (MCF).

Summary of the Invention

[0004] Inertial Confinement Fusion (ICF) uses high - energy lasers or particle beams to compress and heat small pellets of hydrogen fuel, causing nuclear fusion. The fuel is usually a mixture of deuterium (D) and tritium (T), which are isotopes of hydrogen. The fuel is placed in a small spherical capsule called a hohlraum and positioned at the center of a chamber filled with high - energy lasers or particle beams. When the laser or particle beam is fired at the hohlraum, uniform X - rays are emitted, heating and compressing the fuel inside the hohlraum uniformly. This causes the fuel to reach the temperature and pressure conditions necessary for nuclear fusion.

[0005] The main advantage of ICF is that it has the potential to cause nuclear fusion reactions with a relatively small amount of fuel and at a relatively low cost. However, this process is still in the experimental stage and there are significant technical challenges to overcome before it can be considered a practical energy source.

[0006] Magnetic Confinement Fusion (MCF) uses strong magnetic fields to confine and heat a plasma (a hot, ionized gas) of hydrogen fuel in a container for nuclear fusion. The most common type of MCF is called a tokamak fusion, which uses a toroidal (doughnut - shaped) container to confine the plasma. The plasma is held at the center of the chamber by a strong magnetic field, which is created by passing an electric current through coils wound around the chamber. The plasma is heated by injecting energy into it using particle beams or electromagnetic waves.

[0007] The main advantage of MCF is that it has the potential to produce nuclear fusion reactions on a larger scale and is suitable for power generation. However, MCF is a more complex and costly process than ICF, and there are still significant technical challenges to overcome before it can be considered a practical energy source.

[0008] Both inertial confinement fusion (ICF) and magnetic confinement fusion (MCF) have made great progress in recent years, and there are several experimental facilities around the world working on these technologies. However, achieving a sustainable fusion reaction with net energy generation (meaning that the energy produced by the fusion reaction is greater than the energy required to initiate and sustain the reaction) remains a major technical challenge.

[0009] Other approaches to fusion energy, such as magnetized target fusion and muon-catalyzed fusion, are also being studied. However, these approaches are still in the early stages of development. Whether fusion energy can be a viable energy source is still not clear.

[0010] From the above, fusion energy has the potential to be a clean and abundant energy source, but significant technical challenges must be overcome for it to be considered a practical energy source.

Means for Solving the Problems

[0011] According to the present invention, a technology related to fusion energy generation is provided. In particular, the present invention provides fuel pellets for fusion energy and related methods. More specifically, the present invention provides fuel pellets having different ignition temperatures capable of ignition and thermonuclear combustion from a laser fusion system that maximizes the fusion gain while mitigating neutron emission. By way of example only, the present invention can be applied to various applications including electric power energy generation, spacecraft, means of transportation, other vehicles on land, in the air, and on water, defense applications (e.g., satellites, aerospace, land and missile defense, submarines, boats), biotechnology, chemistry, machinery, electricity, communication, and / or data applications.

[0012] In one example, the present invention provides a fusion fuel target device for inertial confinement fusion (ICF). This device has a first fuel material region characterized by a first ignition temperature and a second fuel material region coupled to the first fuel material region. The device has a third fuel material region configured such that the first fuel material region is sandwiched between the second fuel material region and a third material fuel region. In one example, the second fuel material is configured within a central region and has an ignition temperature higher than that of the first fuel material region. In one example, the third fuel material region is an outer region and has an ignition temperature higher than that of the first fuel material region.

[0013] In another example, the present invention provides a spherical target device for inertial confinement fusion. This device has a plurality of multilayer fuels, and the outermost fuel layer is composed of pB11, pB10, or a material containing at least pB11 or pB10.

[0014] In one example, the present invention provides a fuel target device for, for example, an inertial confinement fusion process. This device has a central region including a first fuel material region characterized by a minimum ignition temperature or energy. The device has a second outer region surrounding the central region and including a second fuel material region characterized by an ignition temperature or energy higher than the minimum ignition temperature or energy of the first fuel material region. The device also optionally has a third outer region surrounding the second outer region and including a third fuel material region characterized by an ignition temperature or energy higher than the high ignition temperature or energy of the second fuel material region, and optionally a fourth outer region surrounding the third outer region and including a fourth fuel material region characterized by an ignition temperature or energy higher than the high ignition temperature or energy of the third fuel material region.

[0015] In another example, the present invention provides a fusion fuel target device for inertial confinement fusion (ICF). This device comprises a first fuel material region characterized by a first ignition temperature, and the first fuel material region is bonded to a second fuel material region. Optionally, the device comprises a third fuel material region configured such that the first fuel material region is sandwiched between the second fuel material region and the third fuel material region. The second fuel material is configured within a central region and has an ignition temperature higher than that of the first fuel material region. In one example, the third fuel material region is an outer region and has an ignition temperature higher than that of the first fuel material region.

[0016] Various benefits and advantages are achieved. In one example, the present invention provides clean energy with high efficiency (low ignition temperature) and without generating a large amount of neutrons. In other examples, the present invention uses two abundant and stable elements, hydrogen and boron, as fusion fuels. In one example, this invention provides a cost-effective and efficient method for producing fusion energy without using a large amount of rare deuterium or tritium. In addition to the economic aspect, in the fusion reaction of hydrogen and boron, no neutrons are generated as by-products. These as well as other benefits and advantages are achievable by the present device and related methods. The details of these benefits and advantages are described throughout this specification and more specifically below.

[0017] For a further understanding of the nature and advantages of the present invention, reference may be made to the latter part of this specification and the accompanying drawings.

Brief Description of the Drawings

[0018] To more fully understand the present invention, reference is made to the accompanying drawings. It should be understood that these drawings are not to be construed as limiting the scope of the invention. In one currently described embodiment, the accompanying drawings are used to more specifically describe the best mode of the invention as currently understood.

[0019]

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DETAILED DESCRIPTION OF THE INVENTION

[0020] According to the present invention, technologies related to nuclear fusion energy generation are provided. In particular, the present invention provides fuel pellets for nuclear fusion energy and related methods. More specifically, the present invention provides fuel pellets with a low ignition temperature that minimize the generation of neutrons from a laser fusion system. By way of example only, the present invention can be applied to various applications including energy generation for power, spacecraft, means of transportation, other vehicles on land, water, and air, defense applications (e.g., satellites, aerospace, land and missile defense, submarines, boats), biotechnology, chemistry, machinery, electricity, communication, and / or data applications.

[0021] The present invention relates to a nuclear fusion fuel target for inertial nuclear fusion, and a novel configuration of the fuel layer is adopted. This target design combines one or more favorable characteristics of various nuclear fusion fuels such as, for example, DT (deuterium-tritium), DLi6 (deuterium-lithium 6), and p-(or H-)11B (proton-boron 11) with other materials to achieve a reduction in ignition temperature, minimization of neutron generation, and high-density compression, introducing new functionality to the nuclear fusion fuel target for inertial nuclear fusion. This innovative target design aims to improve the efficiency and feasibility of nuclear fusion in an inertial nuclear fusion system. And this patent relates to an improvement of a previously filed patent idea.

[0022] The disclosed target is characterized by a novel configuration in which a central fuel material region having the lowest ignition temperature or energy compared to other fuel materials is sandwiched between other fuel material regions having higher ignition conditions. This configuration enables the compression of the laser implosion plasma to even higher densities and temperatures by the implosion driven by thermonuclear combustion. Also, the outermost region of the fuel material functions as a neutron / charged particle converter layer, and this neutron / charged particle converter layer is designed to efficiently convert the high kinetic energy of neutrons generated during the fusion reaction into the kinetic energy of charged particles. By this converter layer, the kinetic energy of the neutron flux is converted into the kinetic energy of a charged particle flux such as hydrogen atoms or low atomic number particles that efficiently collide with neutrons, thereby effectively reducing the emission of high-energy neutrons from the target.

[0023] This approach addresses the challenges of conventional ICF targets, provides a more efficient means of achieving fusion ignition, and mitigates the adverse effects associated with the excessive generation of high-energy neutrons. This patent outlines various embodiments, including combinations of different fuel materials and laser parameters, to maximize the gain / energy efficiency of thermonuclear fusion and mitigate the emission of high-energy neutrons from the target. Furthermore, the disclosed target can be configured in a spherical or various spatial geometries, providing flexibility in its applications.

[0024] This patent represents an advancement in fusion fuel target design, enabling more efficient inertial fusion by reducing neutron emission, contributing to improved flexibility and service life in fusion reactor design, efficient maintenance of laser fusion reactor systems, or reduced radioactive contamination of reactor vessels.

[0025] A detailed description of the present invention is provided throughout this specification and in further detail below.

[0026] The target materials are D (deuterium) T (tritium), D (deuterium) Li6 (Lithium), P(proton)B 11 It has been made of a single material composed of binary compounds such as (boron). However, when using a single material of binary compound as a target, there are limitations as described below.

[0027] When using a single material of DT as a target, high-energy neutrons harmful to all materials are generated. Also, T(tritium) is a radioactive substance. The advantage of this DT is the lowest ignition temperature of 13.6 keV. Because of the lowest ignition temperature, currently, more than 90% of conventional fusion companies and U.S. national research institutes are using DT as a target.

[0028] DLi 6 When using a single material composed of as a target, medium-energy neutrons, T(tritium), protons, and other particles are generated. The number and energy of neutrons are much smaller than those of DT. DLi 6 The ignition temperature of is 66 keV, a medium value, much higher than 13.6 keV of DT. DLi 6 Because of the high ignition temperature of DLi 6 has not been desired as a target among scientists.

[0029] pB 11 When using a single material composed of as a target, neutrons are not generated. pB 11 is the safest target material among all kinds of target materials. However, pB 11 has the highest ignition temperature of 123 keV, which is much higher than 13.6 keV of DT and 66 keV of DLi 6 Because of this highest ignition temperature, pB 11 target, although it is the safest material from the perspective of environmental problems, has not been popular among scientists as a target.

[0030] Considering the advantages of each target material, a new target structure combining these materials was invented as described below.

[0031] Various ignition temperatures (T) are shown in Table 1 below.

[0032]

Table 1

[0033] DT has an ignition temperature of 13.6 keV, the lowest. p(H)Li 6 has an ignition temperature of 66 keV, the second lowest. Next, p(H)B 11 has an ignition temperature of 123 keV, the highest. The ignition temperature is basically determined by the atomic number (Z). When the atomic number is small, the charge of the proton is small, so the ignition temperature or energy is low. The DT reaction with atomic number Z = 1 has the lowest ignition temperature. pB with Z = 5 11 has the highest ignition temperature. pLi with Z = 3 6 , pLi 7 , DLi 6 or DLi 7 is considered to have a medium ignition temperature.

[0034] Further details of this technology are described throughout this specification and specifically below.

[0035] Figure 1 is a schematic diagram showing a target used in inertial confinement fusion (ICF) in an example according to the present invention. The target structure is characterized by a layered structure in which the DT fuel in the first fuel region having the lowest ignition temperature of 13.6 keV is sandwiched between DLi in the second fuel region having an ignition temperature higher than that of DT, 66 keV 6 and pB in the third fuel region having an ignition temperature higher than that of DT, 123 keV. 11 In this target structure, since the DT in the first fuel region has the lowest ignition temperature, the pulse width is from 1 ns to 40 ns, and the total pulse power density (total pulse output density) on the target including fluctuations is 1×10 13W / cm 2 from 1 × 10 20 W / cm 2 When the target is compressed by at least 100 times to 20,000 times (or more) by a nanosecond pulsed laser, nuclear fusion ignition density, temperature, and ignition are achieved by nanosecond pulsed laser-driven implosion, and thermonuclear combustion of the first fuel material layer composed of DT starts first (including various variations).

[0036] Next, by the implosion driven by the energy of the thermonuclear combustion of DT in the first fuel region, DLi in the second fuel region 6 is compressed until it reaches a higher density and temperature. When the temperature of the compressed DLi in the second fuel region 6 exceeds the ignition reference value of 66 keV, DLi in the second fuel region 6 ignites, and nuclear fusion energy is released by the thermonuclear combustion of DLi 6 , heating the first fuel region and the second fuel region to a higher temperature. Next, when the temperature of the compressed p(H)B in the third fuel region 11 exceeds the ignition temperature of 123 keV, p(H)B in the third fuel region 11 is ignited.

[0037] pB 11 In the nuclear fusion reaction of pB, particularly among other by-products, hydrogen atoms and boron atoms with low atomic numbers and charges are generated. These ionized hydrogen atoms and boron atoms collide with neutrons generated from the nuclear fusion reactions of DT and DLi 6 and the high kinetic energy of the neutrons is transferred as high kinetic energy to charged particles such as hydrogen atoms and boron atoms. Thus, with this new target design, the generation of high-energy neutrons is reduced or minimized.

[0038] The outermost region made of the third fuel region material has a material layer containing hydrogen atoms or low atomic number atoms designed as a converter layer. When neutrons generated during the fusion reaction collide, it accepts the momentum of the neutrons and converts it into the kinetic energy of charged particles such as hydrogen atoms or low atomic number particles, and escapes the charged particles outward from the target. Therefore, for example, instead of pB 11 solid hydrogen (H) is used as a converter. In this case, hydrogen ignition does not occur. Charged hydrogen atoms collide with neutrons, and neutron generation is reduced or minimized as described above.

[0039] Using this technology, the ignition temperature is as low as 13.6 keV for DT, and when pB 11 is used as the converter layer, neutron generation is minimized. This ignition technology uses a nanosecond pulse laser for implosion and ignition and is called the central ignition method.

[0040] Figure 2 shows a schematic diagram of a fast ignition method with picosecond or femtosecond pulses added for ignition according to an embodiment of the present invention. In this case, the target is compressed by at least 100 times to 20,000 times by a nanosecond pulse laser with a pulse width of 1 ns to 40 ns and a total pulse power density on the target of 1×10 13 W / cm 2 to 1×10 18 W / cm 2 . After the compression of the target, the compressed plasma is externally heated with a picosecond or femtosecond laser to achieve the fusion ignition temperature, and thermonuclear combustion of DT in the first fuel material layer is performed. Here, by focusing the laser beam to 10 to 50 microns on the target, a total peak laser power density of 1×10 17 W / cm 2 to 1×10 24 W / cm 2 is obtained. After the ignition of DT in the first fuel region, as described above, DLi 6 and pB 11 are continuously ignited.

[0041] Using this technology, the ignition temperature is as low as 13.6 keV of DT, and also, by passing through pB as the converter layer, the generation of neutrons can be minimized. This ignition method is called the fast ignition method, which uses a nanosecond pulse laser for compression and picosecond or femtosecond pulses for ignition. 11 By doing so, the generation of neutrons can be minimized. This ignition method is called the fast ignition method, which uses a nanosecond pulse laser for compression and picosecond or femtosecond pulses for ignition.

[0042] Figure 3 is a schematic diagram showing a fast ignition method using additional picosecond or femtosecond pulses for ignition according to an embodiment of the present invention. This target configuration is DLi of the first fuel region having the lowest ignition temperature of 66 keV 6 The fuel is pB of the second fuel region having an ignition temperature higher than that of DT, which is 123 keV 11 and pB of the third fuel region having an ignition temperature higher than that of DT, which is 123 keV 10 and is characterized by a layered structure sandwiched therebetween.

[0043] In this structure, the target is compressed at least 100 times to 20,000 times by a nanosecond pulse laser with a pulse width of 1 ns to 40 ns and a total pulse power density on the target of 1×10 13 W / cm 2 to 1×10 18 W / cm 2 After the compression of the target, as shown in Figure 3, a picosecond or femtosecond laser is directly incident on the DLi of the first fuel region through a conical groove, and the nuclear fusion ignition temperature is achieved by externally heating the compressed plasma, and thermonuclear combustion of the first fuel material layer composed of DLi 6 is carried out. Here, by focusing the laser beam to 10 to 50 microns on the conical groove, the total laser peak density is 1×10 6 W / cm 17 to 1×10 2 W / cm 24 to 1×10 2 W / cm 6includes a tip portion configured in the vicinity or inside of. The outer surface of the conical groove is coated with a high-Z metal material such as gold (Au), lead (Pb), titanium (Ti), or an alloy thereof. In this case, the picosecond or femtosecond pulsed laser is more effective than the case of FIG. 2 in reaching DLi through the conical groove 6 is directly irradiated to. In the case of FIG. 2, the picosecond or femtosecond pulsed laser is irradiated from the surface of pB 11 to the target. Therefore, a part of the laser light may be absorbed or scattered by pB 10 in the third fusion region and reach DLi6 in the first fuel region. After DLi 6 in the first fuel region is ignited, as shown in FIG. 1, DLi 6 and pB 10 are continuously ignited.

[0044] Using this technology, the ignition temperature is as low as 66 keV for DLi 6 , and as shown in FIG. 1, the generation of neutrons is minimized through pB 10 which is a converter layer. This ignition method is called a fast ignition method that uses a nanosecond pulsed laser for compression and a picosecond or femtosecond pulse for ignition.

[0045] FIG. 4 is a schematic diagram showing a fast ignition method using a novel target according to an embodiment of the present invention and using an additional picosecond or femtosecond pulse for ignition. This target configuration has a DT fuel in the first fuel region with the lowest ignition temperature of 13.6 keV, DLi 6 in the second fuel region with an ignition temperature higher than DT of 66 keV, and pB 11 in the third fuel region with an ignition temperature higher than DT of 123 keV, and is characterized by a layered structure sandwiched therebetween.

[0046] In this structure, the pulse width is from 1 ns to 40 ns, and the total pulse power density is from 1×10 13 W / cm 2 to 1×10 18 W / cm 2By a nanosecond pulsed laser, the target is compressed by at least 100 times to 20,000 times (and more). After the compression of the target, as shown in FIG. 4, by externally heating the compressed plasma directly existing on the DT fuel of the first fuel material layer through a conical groove using a picosecond or femtosecond laser, the nuclear fusion ignition temperature is achieved, and thermonuclear combustion of DT in the first fuel material layer is carried out. Here, by concentrating the laser beam within 10 - 50 microns in the conical groove, the total peak laser power density reaches from 1×10 17 W / cm 2 to 1×10 24 W / cm 2 . The conical groove includes a tip formed near or inside the DT of the first fuel material region. In FIG. 4, the conical metal extends outside the target. In this case, the picosecond or femtosecond pulsed laser is more effectively directly irradiated onto the DT through the conical groove than in the case of FIG. 3. In the case of FIG. 3, the picosecond or femtosecond pulsed laser is irradiated onto the target through the conical groove formed on the target surface as shown in FIG. 3. On the surface of the target, plasma is generated by irradiating a nanosecond pulsed laser for compression. Due to the influence of this strong plasma on the surface, in FIG. 3, the picosecond or femtosecond pulsed laser may be prevented from reaching the inside of the cone. On the other hand, when the cone extends outside the target surface as in FIG. 4, the picosecond or femtosecond pulsed laser can reach the inside of the extended cone without being affected by the plasma on the target surface.

[0047] Using this technology, the ignition temperature is as low as 13.6 keV of DT, and as described above, pB 11 can be used as a converter layer to minimize neutron generation. This ignition method is called the fast ignition method, which uses a nanosecond pulsed laser for compression and a picosecond or femtosecond pulsed laser for ignition.

[0048] Figure 5 is a schematic diagram showing another target used for inertial confinement fusion (ICF) according to the present invention. The structure of this target is such that the DT fuel in the first fuel region with an ignition temperature of 13.6 keV, which is the lowest, is sandwiched between DLi in the second fuel region with an ignition temperature of 66 keV, which is higher than that of DT, 6 and pB in the third fuel region with an ignition temperature of 123 keV, which is higher than that of DT, 11 characterizing a layered structure. In this invention, a shell-like cavity is formed at the center of DLi in the second fuel region for compressing the target and accelerating the plasma of each fuel to a high kinetic energy in the central region. And in the central region of the cavity, the kinetic energy of the plasma becomes internal energy for forming a hot spot and then ignition occurs. In this target structure, since the ignition temperature of DT in the first fuel region is the lowest, when the target is compressed by at least 100 times to 20,000 times by a nanosecond pulsed laser with a pulse width of 1 ns to 40 ns and a total pulse power density of 1×10 6 W / cm 13 ~1×10 2 W / cm 20 first, for DT in the first fuel layer, the nuclear fusion ignition density and temperature are achieved by implosion ignition driven by a nanosecond pulsed laser, and thermonuclear combustion is initiated. 2 Next, DLi in the second fuel region

[0049] is compressed to implode and is ignited by the energy of the thermonuclear combustion of DT in the first fuel region surrounding DLi in the second fuel region. Further, DLi 6 is isotopically compressed by the ignition energy of DT in the first fuel region. Next, p(H)B in the third fuel region 6 is ignited by the energy of the thermonuclear combustion of DLi in the second fuel region. 6 During the nuclear fusion reaction of pB 6 11 hydrogen atoms and boron atoms with a small atomic number and charged are generated. These charged hydrogen atoms and boron atoms are DT and DLi 11

[0050] pB 11 ​6 It collides with neutrons generated from a nuclear fusion reaction, and the high kinetic energy of the neutrons is transferred as kinetic energy to charged particles of hydrogen atoms and boron atoms. Thus, with this new target design, it becomes possible to minimize the generation of high-energy neutrons.

[0051] The outermost region of the third fuel region material includes a material layer containing hydrogen atoms or low-atomic-number atoms designed as a converter layer. When it collides with neutrons generated during a nuclear fusion reaction, it accepts the momentum of the neutrons, converts it into the kinetic energy of charged particles such as hydrogen atoms or low-atomic-number particles, and releases it outward from the target. In one example, pB 11 Solid hydrogen (H) is used as the converter instead of pB. In this case, hydrogen ignition does not occur. Charged hydrogen atoms collide with neutrons, and as described above, neutron generation is reduced or minimized.

[0052] Using this technology, with pB 11 as the converter layer, the ignition temperature is as low as 13.6 keV for DT, and neutron generation is minimized. This ignition method is called the central ignition method, which uses only a nanosecond pulse laser for implosion and ignition.

[0053] The cavity at the center of the second fuel region can be used for other fuel materials in the second fuel region. By using the central ignition method or the fast ignition method using a nanosecond pulse laser, the fuel materials can be easily compressed, and the plasma of each fuel can be accelerated to the central region with high kinetic energy. Then, in the central region of the cavity, the kinetic energy of the plasma becomes internal energy to form a hot spot, and then ignition occurs.

[0054] Figure 6 is a schematic diagram showing another target used for inertial confinement fusion (ICF) according to an example of the present invention. The target configuration is such that the DT fuel in the first fuel region having the lowest ignition temperature of 13.6 keV and the DLi in the second fuel region having an ignition temperature of 66 keV higher than DT 6and further, pB of a third fuel region having an ignition temperature of 123 keV, which is higher than that of DT 11 or pB 10 and is characterized by a layered structure sandwiched therebetween. In this target structure, pB of the third fuel region 11 or pB 10 is composed of a foam structure or a porous structure, or is contained in a foam material or a porous material. The nanosecond pulsed laser is directly irradiated onto DT of the first fuel region through multiple reflections from the pores of the foam structure or the porous structure, or directly through the pores. Therefore, the nanosecond pulsed laser is effectively irradiated onto the DT fuel of the first fuel region as compared with the case of FIG. 1. Since the DT of the first fuel region is directly irradiated with the laser and the ignition temperature of DT is the lowest, when the target is compressed at least 100 times to 20,000 times by a nanosecond pulsed laser having a pulse width of 1 ns to 40 ns and a total pulse output density on the target of 1×10 13 W / cm 2 ~1×10 20 W / cm 2 nuclear fusion ignition density and temperature are achieved by nanosecond pulsed laser-driven implosion and ignition, and thermonuclear combustion in the first fuel material layer of DT is initiated first.

[0055] Next, DLi of the second fuel region 6 is compressed so as to implode, and is ignited by the energy of thermonuclear combustion of DT in the first fuel region surrounding DLi of the second fuel region 6 , and further DLi 6 is isotopically compressed by the ignition energy of DT in the first fuel region. Thereafter, p(H)B 6 of the third fuel region or pB 11 or pB 10 is ignited by the energy of thermonuclear combustion of DLi of the second fuel region.

[0056] pB composed of a foam structure or a porous structure, or contained in a foam material or a porous material 11 or pB 10Through the fusion reaction, charged hydrogen atoms and boron atoms with low atomic numbers are generated. These charged hydrogen atoms and boron atoms are DT and DLi 6 Collide with the neutrons generated from the fusion reaction, and then the kinetic energy of the neutrons is transferred as high kinetic energy to the charged particles of the hydrogen atoms and boron atoms. In this way, with this new target design, the generation of high-energy neutrons is minimized.

[0057] The outermost region of the third fuel region material is composed of a material layer containing hydrogen atoms or low atomic number elements after ignition and is designed as a converter layer. When this layer collides with the neutrons generated during the fusion reaction, it receives the momentum of the neutrons, converts it into the kinetic energy of charged particles such as hydrogen atoms or low atomic number particles, and the charged particles leak out of the target to the outside. In one example, pB 11 or pB 10 Solid hydrogen (H) is used as the converter instead. In this case, hydrogen ignition does not occur. The charged hydrogen atoms collide with the neutrons, and as described above, the generation of neutrons is reduced or minimized.

[0058] Using this technology, the ignition temperature is as low as 13.6 keV of DT, and by using pB 11 or pB 10 as the converter layer, the generation of neutrons is reduced or minimized. This ignition method is called the central ignition method, which uses only nanosecond pulsed lasers for implosion and ignition.

[0059] Figure 7 is a schematic diagram explaining indirect ignition using a hohlraum according to an example of the present invention. In one example, the target used in Figure 1 is placed inside a cylindrical hohlraum, and then a nanosecond pulsed laser with a pulse width of 1 ns to 40 ns and a total pulse energy of 1 to 10 MJ is irradiated onto the inner surface of the hohlraum through the windows on both sides of the cylindrical hohlraum to generate X-rays. Then, when this X-ray is irradiated into the target for ignition of the target, as shown in Figure 1, first the DT in the first fuel region is ignited, and then DLi 6 and pB11 is continuously ignited.

[0060] Also, on the outer surface of the hallraum, pB 11 , pB 10 or at least pB 11 or pB 10 is coated with a material containing, and high-energy neutrons passing through the hallraum are reduced or blocked. The pB 11 or pB 10 fuel in the third fuel region, when colliding with neutrons generated during the fusion reaction, receives the kinetic energy of the neutrons and functions as a converter layer that converts it into the kinetic energy of charged particles leaking outward from the target as shown in FIG. 1.

[0061] Also, pB 11 , pB 10 or at least pB 11 or pB 10 is coated on the outer surface of the hallraum and functions to shield high-energy neutrons from leaking out of the hallraum. By using the hallraum thus coated, the number of neutrons generated by the ignition of DT and DLi 6 is further reduced.

[0062] When using the present technology from FIG. 1 to FIG. 7 described above, the ignition temperature is as low as 13.6 keV, and when using pB 11 or pB 10 as a converter, the number of neutrons generated by DT ignition is reduced. When using a hallraum coated with pB 11 or pB 10 the number of neutrons generated is further reduced.

[0063] In the above-mentioned present invention, the picosecond pulse laser light source means a laser light source having a pulse width of 1 picosecond to 900 picoseconds. The nanosecond pulse laser light source means a laser light source having a pulse width of 1 nanosecond to 40 nanoseconds. The femtosecond pulse laser light source means a laser light source having a pulse width of 10 femtoseconds to 1000 femtoseconds. The wavelengths of the nanosecond, picosecond, and femtosecond laser light sources are from ultraviolet (340 nm) to infrared (1080 nm).

[0064] In one example, the picosecond laser light source is configured to have laser output uniformity on the wavefront using one or more deformable mirrors or cavity devices (optical resonator devices), and outputs picosecond pulses focused on the target device. In one example, the nanosecond laser light source and the picosecond laser light source are configured to focus on the target using one or more concave mirrors or lenses, and output a plurality of nanosecond pulses and a plurality of picosecond pulses, respectively. In one example, at least one of the nanosecond pulse laser light sources has an emission wavelength, phase, or both wavelength and phase that are different from one or more of the other nanosecond pulse laser light sources.

[0065] In one example, each of the nanosecond pulse laser light sources has an oscillation wavelength, phase, or both wavelength and phase that are different from those of the other nanosecond pulse laser light sources, and realizes minimization of a desired non-coherence or interference effect near the center of the cavity or reactor. In this case, the Fabry-Perot cavity is a plurality of Fabry-Perot cavities configured to form a hub and spoke configuration intersecting at the center of the reactor. In one example, at least one of the plurality of Fabry-Perot cavities has a cavity length different from one or more of the other Fabry-Perot cavities. In one example, each of the Fabry-Perot cavities has a different cavity length.

[0066] In one example, the present invention provides a fusion fuel target device for inertial confinement fusion (ICF). This device has a first fuel material region characterized by a first ignition temperature and a second fuel material region coupled to the first fuel material region. This device includes a third fuel material region configured such that the first fuel material region is sandwiched between the second fuel material region and the third fuel material region. In one example, the second fuel material is disposed within a central region and has an ignition temperature higher than that of the first fuel material region. In one example, the third fuel material region is an outer region and has an ignition temperature higher than that of the first fuel material region.

[0067] In one example, the third fuel material region includes a converter layer that, upon collision with neutrons generated during the fusion reaction, receives the momentum energy of the neutrons, converts that momentum energy into the kinetic energy of charged particles, and causes the charged particles to be emitted from the central region to the outside. In one example, the first fuel material region is configured to ignite before the second fuel material region or the third fuel material region. In one example, the third fuel material region has both the characteristics of a converter and the characteristics of thermonuclear combustion. In one example, the third fuel material region is surrounded by an ablation material that absorbs the incident laser energy and ablates outwardly to drive the implosion. In one example, the third fuel material region is characterized as both a converter and an ablator. In one example, the first fuel material region includes at least one of D (deuterium) T (tritium), DHe 3 , DD, or DLi 6 (deuterium-lithium 6), or DLi 7 (deuterium-lithium 7). In one example, the second fuel material region includes at least one of DHe 3 , DLi 6 (deuterium lithium 6), DLi 7 (deuterium lithium 7), H (hydrogen) Li 6 , HLi 7 , pB 11 , or PB 10 . In one example, the third fuel material region is P (or H) B 11 or pB10 includes at least one of them. In one example, the third fuel material region is (hydrogen) H, P (or H)-B 11 or pB 10 or includes at least one of low atomic number particles.

[0068] In one example, this device has a pulse width from 1 ns to 40 ns, and the total pulse power density irradiated on the device is 1×10 13 W / cm 2 to 1×10 20 W / cm 2 and is exposed to a plurality of nanosecond pulse lasers that compress the device by at least 100 times to 20,000 times simultaneously with the thermonuclear combustion starting in the first fuel material region.

[0069] In one example, while a nanosecond pulse laser with a pulse width from 1 ns to 40 ns and a total pulse power density from 1×10 13 W / cm 2 to 1×10 18 W / cm 2 is irradiated on the device, the thermonuclear combustion in the first fuel material region is initiated by a picosecond or femtosecond laser from outside the device such that the total peak laser power density on the device is from 1×10 17 W / cm 2 to 1×10 24 W / cm 2 This is characterized.

[0070] In one example, the device has other variations. The device includes a conical groove configured inside. In one example, the conical groove includes a tip configured near or inside the first fuel material region. In one example, the conical groove has an outer surface, and the outer surface is coated with a high-Z metal material, which is at least one of gold (Au), lead (Pb), or other suitable high-Z metal materials. In one example, a picosecond laser or a femtosecond laser is irradiated through the conical groove configured inside the device. In one example, the picosecond laser is configured to focus on a laser spot size of 5 microns to 50 microns on the groove configured in the device. In one example, the device is spherical with a diameter of 1 millimeter to 10 millimeters.

[0071] In one example, the device has a material different from any of the first fuel material region, the second fuel material region, or the third fuel material region (collectively referred to as the fuel material regions), and the material is configured between at least a pair of fuel material regions or between any one of the fuel material regions and the ablation material. In one example, a cavity is formed in the central region of the second fuel region.

[0072] In another example, the present invention provides a spherical target device for inertial nuclear fusion. The device includes a plurality of multi-layer fuels, and the outermost fuel layer is made of a material containing pB 11 , pB 10 , or at least pB 11 or pB 10 .

[0073] In one example, the multi-layer fuel is composed of two or three different fuel material layers. The device also includes a conical groove including a tip configured near or inside the DT fuel layer or the DT fuel region configured in one of the plurality of multi-layer fuels. In one example, one of the plurality of multi-layer fuels includes DT configured as the first ignition fuel material. In one example, the device is arranged inside a cylindrical hohlraum. In one example, on the outer surface of the hohlraum, there is pB 11 , PB 10or at least pB 11 or PB 10 A material containing 11 or 10 is coated. In one example, the hohlraum is irradiated with a plurality of nanosecond pulsed lasers having a pulse width of 1 ns to 40 ns and a total pulse energy of 1 to 10 megajoules on the inner surface of the hohlraum, generating X-rays through one or more sides of one or more opening windows of the hohlraum, and the plurality of X-rays irradiate the device for ignition of the device.

[0074] FIG. 8 is a schematic diagram showing a target used for inertial confinement fusion (ICF) according to an example of the present invention. As shown, D (deuterium) T (tritium) Li 6 (DTLi 6 ) or DTLi 7 fuel is the first fuel disposed in the central region of the target. Here, a part of D in DLi 6 or DLi 7 is replaced by T. Surrounding DT, there is a second fuel consisting of p (proton or H (hydrogen)) B 11 (boron 11 ). DTLi 6 or DTLi 7 is solid at room temperature. The ignition temperature of DTLi 6 or DTLi 7 is lower than the ignition temperature of DLi 6 or DLi 7 . This is because DTLi 6 or DTLi 7 is considered to be a mixture of DT and DLi 6 or DLi 7 . Therefore, the ignition temperature of DTLi 6 or DTLi 7 is considered to be between 13.6 keV of DT and 66 keV of DLi 6 . Also, the target gain of DTLi 6 or DTLi 7 is considered to be higher than the target gain of DLi 6 or DLi 7 . This is because DTLi 6 or DTLi 7is a mixture of DT and DLi 6 or DLi 7 This is because the outermost material is an ablation material. A conical groove or a metal cone is formed on the target. The tip of the conical groove or the metal cone is located near or inside the first fuel material composed of DTLi 6 or DTLi 7 A nanosecond pulse with a pulse width of 1 ns to 40 ns and a total pulse power density of 1×10 13 W / cm 2 ~1×10 18 W / cm 2 is irradiated onto the target, and then the target is compressed by at least 100 times to more than 20,000 times by laser ablation.

[0075] In one example, a picosecond or femtosecond laser light source outputs a picosecond or femtosecond pulse focused on the conical groove on the target, and its total peak pulse power density is 1×10 18 W / cm 2 ~1×10 24 W / cm 2 The picosecond laser light source focuses on a small laser spot size of 5 microns to 50 microns on the groove. The target is spherical or cylindrical with a diameter of 1 millimeter to 9 millimeters. Therefore, the dimensions of the conical groove are approximately the same as or slightly larger than the laser spot size. The high-intensity picosecond or femtosecond laser light source directly and effectively irradiates and ignites DTLi 6 or DTLi 7 at a lower ignition temperature between 13.6 keV and 66 keV through the groove. When there is no groove on the target, the high-intensity picosecond laser or femtosecond laser light is blocked from reaching the first fuel composed of DTLi 11 by the second fuel composed of pB 6 or DTLi 7 and cannot effectively ignite DTLi 6 or DTLi 7 And DTLi 6 or DTLi 7Upon ignition, high-energy charged particles and high-energy neutrons are generated as plasma.

[0076] Next, the high-energy charged particles and high-energy neutrons generated by the ignition of DTLi 6 or DTLi 7 are used to ignite the second fuel of pB 6 or pB 7 surrounding DTLi 11 .

[0077] Thereafter, in the ignition reaction of pB 11 , p effectively collides with high-energy neutrons, and the kinetic energy is transferred from the high-energy neutrons to the protons. After the high-energy neutrons lose energy, the low-energy neutrons are absorbed by charged boron (B). And the generation of neutrons is reduced or further minimized by using a new target. By using the present invention, the ignition temperature is as low as between 13.6 keV and 66 keV, the generation of neutrons is reduced or further minimized. Compared with 123 keV when pB 11 is directly ignited by a laser, the ignition temperature of DTLi 6 or DTLi 7 is much lower.

[0078] In one example, the outermost material of the target is an ablation material irradiated with a high-power density nanosecond laser, and the target is strongly compressed inward. The ablation materials include, but are not limited to, Al (28 N / MW), POM polymer (125 N / MW), TaW (31 N / MW), and Au. Delrin (trademark) (POM, polymer, 125 N / MW) is a preferred target material because it has the highest Newton value per megawatt. Also, metals such as Al, TaW, and Au are desirable. When the outer elastic material is a polymer such as perylene, polystyrene, or PVA, the elastic material itself functions as a laser ablation material. In one example, laser ablation is preferably performed under vacuum and operates by inducing a jet of vapor and plasma from the ablation material using a high-intensity nanosecond laser pulse. When a sufficiently powerful pulsed laser beam is irradiated onto the ablation material on the surface of the target, a high-temperature jet is formed. Momentum is the product of mass and the velocity of the target in the inward direction.

[0079] Figure 9 is a schematic diagram showing another target for inertial confinement fusion (ICF) according to an example of the present invention. In the central region of the target, D (deuterium) T (tritium) Li 6 or DTLi 7 fuel is arranged as the first fuel. Surrounding the first fuel consisting of DTLi 6 or DTLi 7 the target has DLi of the second fuel 6 and pB of the third fuel 11 arranged. The outermost material is an ablation material. A conical groove is formed in the target. The tip of the conical groove is located near or inside the first fuel material DTLi 6 or DTLi 7 The pulse width is 1 ns to 40 ns, and the total pulse power density is 1×10 13 W / cm 2 ~1×10 18 W / cm 2A nanosecond pulse is irradiated onto the target, and then the target is compressed by at least 100 times to 20,000 times by laser ablation.

[0080] In one example, a picosecond or femtosecond laser light source outputs picosecond or femtosecond pulses focused on a conical groove on the target, and the total peak pulse power density thereof is 1×10 17 W / cm 2 ~1×10 24 W / cm 2 . The picosecond laser light source focuses on a small laser spot size of 5 microns to 50 microns on the groove. The target is spherical with a diameter of 1 mm to 9 mm. Therefore, the dimensions of the conical groove are approximately the same as or slightly larger than the laser spot size. The high-intensity picosecond or femtosecond laser light source irradiates DTLi 6 or DTLi 7 directly and effectively through this groove and ignites it at a low ignition temperature of 13.6 keV to 66 keV. When there is no groove on the target, the high-intensity picosecond or femtosecond laser light is blocked by DLi 6 of the second fuel and pB 7 of the third fuel from reaching the first fuel composed of DTLi 6 or DTLi 11 or DTLi 6 or DTLi 7 composed of DTLi 6 or DTLi 7 from being effectively ignited. Then, when DTLi

[0081] or DTLi 6 or DTLi 7 is ignited at a temperature between 13.6 keV and 66 keV, high-energy charged particles and high-energy neutrons are generated as plasma. 6 or DTLi 7 of DLi 6is used for ignition at the ignition temperature of 66 keV of the second fuel consisting of. Next, DLi 6 High-energy charged particles, neutrons, and other particles from the ignition reaction of DLi 6 ignite pB, which is the third fuel surrounding DLi 11 at the ignition temperature of 123 keV.

[0082] After that, due to the ignition reaction of pB 11 p effectively collides with high-energy neutrons, and the kinetic energy is transferred from the high-energy neutrons to the protons. After the high-energy neutrons lose energy, the low-energy neutrons are absorbed by the charged boron (B). Therefore, by using the novel target according to the present invention, the generation of neutrons is minimized. By using the present invention, the ignition temperature is as low as between 13.6 keV and 66 keV, and the generation of neutrons is reduced or minimized. DTLi 6 or DTLi 7 The ignition temperature from 13.6 keV to 66 keV of DTLi 11 is much lower compared to 123 keV when pB

[0083] According to the present invention, the novel targets in FIGS. 8 and 9 are composed of materials that are solid at room temperature. DTLi 6 DTLi 7 DLi 6 and pB 11 are all solid at room temperature. According to the present invention, the novel target does not need to be cooled to extremely low temperatures to solidify DT. Also, the cost of the material is much lower than that of DT and is efficient. Therefore, by using this novel target, in one example, the cost of the target is significantly reduced compared to a DT target of $500,000.

[0084] In the above description of the figures, no matter what kind of material is inserted between each fusion material region, or between the fusion material region and / or the ablation material, the technology of the present invention remains unchanged and can be deformed.

[0085] In the description of the above figures, the timing between the irradiation of the picosecond or femtosecond laser light source and the nanosecond pulse laser light source is as follows in any case. The pulse width is 1 ns to 40 ns, and the total pulse peak power density is 1×10 13 W / cm 2 ~1×10 18 W / cm 2 of the nanosecond pulse laser is irradiated into the target, and while the target is compressed at least 100 times to 20,000 times by laser ablation, the picosecond or femtosecond laser light source focuses on the conical groove on the target, and the total peak pulse power density is 1×10 17 W / cm 2 ~1×10 24 W / cm 2 of picosecond or femtosecond pulses is output.

[0086] As shown in FIG. 3, according to the present invention, a shell (outer shell) composed of a fusion fuel and an ablator is adopted, and an external laser incident hole is provided in the shell. The target can be used as long as it is a general one used in inertial fusion regardless of indirect irradiation or direct irradiation. As the initial target shape, a target having a hollow structure at the target center is suitable for the present invention. More preferably, DTLi 6 or DTLi 7 , DLi 6 , DLi 7 , pB 11 and the like are used as a target having a multilayer structure. These targets, as shown in FIG. 10, not only attach a conical target made of a high atomic number material such as gold, lead, titanium or a compound thereof, but also introduce an external laser into the cavity through the laser incident hole of the shell and use it, so that laser incidence can be protected from the interference of the imploded plasma.

[0087] In the technology of the present invention shown in FIG. 10, a heating laser is introduced into the cavity in the fuel target during the implosion process through a laser entrance hole provided in the target from an external source. The incidence timing of the heating laser coincides with the timing when the implosion speed is maximum or nearly maximum while the cavity still exists at the center of the implosion acceleration stage.

[0088] By introducing the external heating laser into the cavity at this crucial timing, the inner surface of the shell during implosion is heated, and ablation occurs towards the center of the cavity. The released plasma collides in the central region to form a high-temperature hot spark. The implosion deceleration stage starts from this point. The laser energy supplied from the external source passes through the kinetic energy of the ablated plasma and finally becomes the internal energy of the high-temperature hot spark. As a result, in this approach, the energy required for the formation of the hot spark, which is essential for nuclear fusion ignition, can be efficiently supplied from the external source to the hot spark. This method is a unique feature not seen in the conventional central ignition method or fast ignition method.

[0089] Since energy can be supplied to the hot spark from the outside very efficiently in this way, it is possible to form a hot spark with less total laser energy compared to the central ignition method and the fast ignition method. This enables nuclear fusion ignition and combustion with less laser energy. This technology is called the Inner Irradiation Method.

[0090] Furthermore, the inner irradiation method addresses the suppression of the destabilization of hot spark formation due to the Rayleigh-Taylor instability in the implosion deceleration stage, which is the most significant issue in inertial nuclear fusion. At this stage, the hot spark formed in the center decelerates the implosion motion of the surrounding imploding fuel. In this situation, the Rayleigh-Taylor instability may occur at the interface between the hot spark and the surrounding main fuel layer, which is the imploding fuel.

[0091] Furthermore, the heating laser used in this technology does not require an ultra-high intensity laser with pulses of femtoseconds (fs) or less than 10 picoseconds (ps), which are commonly used in conventional fast ignition technologies. Instead, a relatively long pulse of about 100 picoseconds (ps) can be utilized, which is the value obtained by dividing the radius of the cavity by the ablation velocity of the inner surface of the heating shell. In conventional fast ignition, it was necessary to heat within a time frame determined by the inertia until the high-density plasma collapsed. However, in our approach, it is sufficient to introduce the heating laser from the inside while the cavity exists, and the existence period of the cavity can be extended to the hundreds of picosecond level by controlled implosion. A pulse of about 100 picoseconds can be generated by conventional nanosecond laser technology without the need for ultra-high intensity laser technology typified by Chirped Pulse Amplification (CPA).

[0092] Figure 10 shows an example of the present invention using a novel target and an internal irradiation method. There is a relatively large cavity in the central region of the target, and the size of the cavity is determined by the pulse width of the picosecond pulse. The smaller the pulse width of the picosecond pulse, the smaller the size of the cavity. The innermost fuel is D (deuterium) T (tritium) Li as the first fuel 6 or DTLi 7 which is the first fuel. Surrounding the first fuel DTLi 6 or DTLi 7 there is a second fuel composed of DLi 6 fuel, and a third fuel composed of pB 11 . The outermost material is an ablation material, which is not shown in the figure. Alternatively, pB 11 can function as an ablator even without an ablator layer. A conical groove and a metal cone are formed on the target. The tip of the metal cone is located near or inside the first fuel material of DTLi 6 or DTLi 7 . The pulse width is 1 ns to 40 ns, and the total pulse power density is 1×10 13 W / cm 2 ~1×10 18 W / cm2 A nanosecond pulse is irradiated into the target, and then the target is compressed by at least 100 times to 20,000 times by laser ablation.

[0093] The picosecond laser light source outputs a picosecond pulse focused on a conical groove on the target, and its total peak pulse energy is 100 kJ to 1 MJ, and the pulse width is 50 ps to 900 ps. cm 2 . The picosecond laser light source is focused on a small laser spot size of 5 microns to 50 microns on the cone. The target is spherical or cylindrical with a diameter of 1 mm to 9 mm. Therefore, the dimensions of the conical groove or the metal cone are approximately the same as or slightly larger than the laser spot size. The high-intensity picosecond laser light source, as shown in FIG. 2, has a low ignition temperature between 13.6 keV and 66 keV through the metal cone, groove, and cavity for DTLi 6 or DTLi 7 and irradiates and ignites directly and effectively on the inner wall of DTLi 6 or DTLi 7 . When DTLi

[0094] or DTLi 6 is ignited, high-energy charged particles and high-energy neutrons are generated as plasma. 7 The high-energy charged particles and high-energy neutrons generated by the ignition of DTLi 6 or DTLi 7 are used to ignite the second fuel of DLi 6 surrounding DTLi 6 at an ignition temperature of 66 keV. And these high-energy charged particles, neutrons and other particles generated by the ignition reaction of DLi 6 are used to ignite pB 11 , the third fuel surrounding DLi

[0095] at an ignition temperature of 123 keV. 11Through the ignition reaction, p effectively collides with high-energy neutrons, and the kinetic energy is transferred from the high-energy neutrons to the protons. As a result, by using the novel target of the present invention, the generation of neutrons is minimized. By using the present invention, the ignition temperature is as low as between 13.6 keV and 66 keV, and the generation of neutrons is also minimized. Also, DTLi 6 or DTLi 7 The ignition temperature of 13.6 keV to 66 keV is much lower than 123 keV when pB 11 is directly ignited by a laser.

[0096] As an example, the novel target in FIG. 10 is composed of materials in a solid state at room temperature. DTLi 6 , DTLi 7 , DLi 6 , pB 11 All the materials are solids at room temperature. This novel target does not need to be cooled to extremely low temperatures to solidify DT. Also, the cost of these materials is much lower than that of DT. Therefore, by using the novel target of the present invention, the target cost is dramatically reduced compared to, for example, the cost of a 0.5 M dollar DT target.

[0097] In the above technology shown in FIG. 10, the claims of the present invention are not changed no matter what kind of materials are inserted between the fusion material regions or between the fusion material regions and / or the ablation materials.

[0098] In the above technology shown in FIG. 10, the irradiation timing between the picosecond laser light source and the nanosecond pulse laser light source is a pulse width of 1 ns to 40 ns, and the total pulse peak power density is 1×10 13 W / cm2 to 1×10 18 W / cm 2Irradiate the target with nanosecond pulses, and while the target is compressed by at least 100 to 20,000 times by laser ablation, the picosecond laser light source outputs picosecond pulses with a total peak pulse energy of 100 kJ to 1 MJ focused on the metal cone on the target. However, there may be variations.

[0099] In the example of FIG. 11, the present invention provides a fusion fuel target device for inertial confinement fusion (ICF). This device has a first fuel material region characterized by a first ignition temperature and a second fuel material region coupled to the first fuel material region. This device includes a third fuel material region configured such that the first fuel material region is sandwiched between the second fuel material region and the third fuel material region. As an example, the second fuel material is disposed within the central region and has an ignition temperature higher than that of the first fuel material region. Also, as an example, the third fuel material region is disposed in the outer region and has an ignition temperature higher than that of the first fuel material region.

[0100] In the example of FIG. 12, the third fuel material region includes a converter layer. When this layer collides with neutrons generated during the fusion reaction, it receives the kinetic energy of the neutrons and converts it into the kinetic energy of charged particles so that the charged particles escape from the central region to the outside. As an example, the first fuel material region is configured to be ignited earlier than the second fuel material region or the third fuel material region. As an example, the third fuel material region is characterized by both a converter and thermonuclear combustion. As an example, the third fuel material region is surrounded by an ablation material that absorbs the incident laser energy and drives implosion by ablating outward. As an example, the third fuel material region is characterized as both a converter and an ablator. As an example, the first fuel material region includes at least one of D (deuterium) T (tritium) Li (lithium) 6 or DTLi 7 and. As an example, the second fuel material region is DLi 6 (deuterium-lithium 6 ) or DLi7 (Deuterium - Lithium 7 ) includes at least one of. As an example, the third fuel material region is (hydrogen) H, p (or H) B 11 , pB 10 , or includes at least one of low atomic number particles.

[0101] In the example of FIG. 11, the device is irradiated with a plurality of nanosecond pulsed lasers with a pulse width of 1 ns to 40 ns and a total pulse power density of 1×10 13 W / cm 2 ~1×10 20 W / cm 2 , and when thermonuclear combustion is initiated in the first fuel material region, it is compressed by at least 100 times to 20,000 times simultaneously.

[0102] As an example, this device is characterized by thermonuclear combustion in the first fuel material region, and this thermonuclear combustion occurs while a nanosecond pulsed laser with a pulse width of 1 ns to 40 ns and a total pulse power density of 1×10 13 W / cm 2 ~1×10 18 W / cm 2 is irradiated on the device, and is ignited by a picosecond or femtosecond laser from outside the device having a total peak laser power density of 1×10 17 W / cm 2 ~1×10 24 W / cm 2 .

[0103] As an example, the device has other variations. The device has a conical groove configured within the device. As an example, the conical groove has a tip, and the tip is disposed near or within the first fuel material region. As an example, the conical groove has an outer surface, and the outer surface is coated with a metallic material having a high Z value. The metallic material is at least one of gold (Au), lead (Pb), and other suitable high Z metallic materials. As an example, a picosecond or femtosecond laser is irradiated through the conical groove configured within the device. As an example, the picosecond laser is configured to focus on the groove configured in the device with a laser spot size of 5 microns to 50 microns. As an example, the device is spherical with a diameter of 1 millimeter to 10 millimeters.

[0104] As an example, the device has a material different from any of the first fuel material region, the second fuel material region, or the third fuel material region (collectively referred to as the fuel material region), and this material is disposed between at least a pair of fuel material regions or between any of the fuel material regions and the ablation material. As an example, a cavity is formed in the central region of the second fuel region.

[0105] As an alternative example, the present invention provides a spherical target device for inertial nuclear fusion. This device includes a plurality of multi-layer fuels, and the outermost fuel layer is made of a material containing pB 11 , pB 10 , or at least pB 11 or pB 10 and is composed of the material.

[0106] As an example, the multi-layer fuel is composed of two or three different fuel material layers. This device also has a conical groove with a tip configured near or within the DTLi 6 or DTLi 7 fuel layer or region. This tip is disposed in one of the plurality of multi-layer fuels. As an example, one of the plurality of multi-layer fuels is DTLi 6 or DTLi 7 configured as the first ignition fuel material.It includes. As an example, the device is arranged inside a cylindrical hallraum. As an example, pB 11 , PB 10 , or at least pB 11 or PB 10 A material containing is coated on the outer surface of the hallraum. As an example, the hallraum is irradiated on the surface of the internal region of the hallraum with a plurality of nanosecond pulsed lasers with a pulse width of 1 ns to 40 ns and a total pulse energy of 1 to 10 megajoules, generates X-rays through one or more surfaces of one or more opening windows of the hallraum, and irradiates the device with a plurality of X-rays to ignite the device.

[0107] As an example, FIG. 11 is a schematic diagram showing a target used in inertial confinement fusion (ICF) in an example according to the present invention. The target configuration features a layer structure, and the DTLi of the first fuel region having the lowest ignition temperature among the entire fuel layer 6 or DTLi 7 is sandwiched between DLi of the second fuel region having an ignition temperature of 66 keV higher than DTLi 6 or DTLi 7 and pB11 of the third fuel region having an ignition temperature of 123 keV higher than DTLi 6 and DTLi 6 . DTLi 6 or DTLi 7 is a chemical composition in which a part of D of DLi 6 or DTLi 7 is replaced by T, and as long as DTLi 6 or DTLi 7 can exist as a solid substance before laser irradiation, the atomic number fraction of T in DTLi 6 or DTLi 7 is arbitrary. In this target structure, since DTLi of the first fuel region 6 or DTLi 7 has the lowest ignition temperature, the target has a pulse width of 1 ns to 40 ns and a total pulse power density on the target of 1×10 13 W / cm 2 ~1×10 20 W / cm 2When compressed by at least 100 times to 20,000 times (or more, including variations) by a nanosecond pulsed laser, nuclear fusion ignition density and temperature are achieved using implosion and ignition driven by a nanosecond pulsed laser, and DTLi, which is the first fuel material layer 6 or DTLi 7 starts thermonuclear combustion first. This method is called the Center Ignition Method.

[0108] As an example, FIG. 12 is a schematic diagram showing another target used in inertial confinement fusion (ICF) in an example according to the present invention. The target configuration features a layer structure, and DTLi in the first fuel region with the lowest ignition temperature among the entire fuel layer 6 is DTLi 6 sandwiched between DLi in the second fuel region having an ignition temperature of 66 keV higher than DTLi 6 and pB in the third fuel region having an ignition temperature of 123 keV higher than DTLi 6 DTLi 11 is a chemical composition in which part of the D in DLi 6 is replaced by T. As long as DTLi 6 can exist as a solid substance before laser irradiation, the atomic ratio of T in DTLi 6 is arbitrary. In the present invention, a shell-shaped cavity for compressing the target and accelerating the plasma of each fuel to a high kinetic energy toward the central region is formed at the center of DLi in the second fuel region 6 . Then, the kinetic energy of the plasma becomes internal energy in the central region of the cavity to form a hot spot and then ignite. In this target structure, since DTLi in the first fuel region 6 has the lowest ignition temperature, the target has a pulse width of 1 ns to 40 ns and a total pulse power density on the target of 1×10 6 W / cm 13 ~1×10 2 W / cm 20 ~1×10 2When compressed by at least 100 to 20,000 times (or more) by a nanosecond pulsed laser (including variations), nuclear fusion ignition density and temperature are achieved by nanosecond pulsed laser-driven implosion and ignition, and the DTLi, which is the first fuel material layer 6 starts thermonuclear combustion first. This method is called the central ignition method.

[0109] The current technology of the novel targets in FIGS. 4 and 5 is composed of materials in a solid state at room temperature. DTLi 6 DTLi 7 DLi 6 pB 11 All of the materials are solids at room temperature. The novel targets of this technology do not need to be cooled to extremely low temperatures to make solid DT. Also, the cost of these materials is much lower than the cost of DT. Therefore, by using the novel targets of this technology, the target cost is significantly reduced compared to, for example, $0.5 million for a DT target.

[0110] As an example, a picosecond laser light source is configured to have laser power uniformity of the wavefront using one or more deformable mirrors or cavity devices and outputs picosecond pulses that are focused on a target device. As an example, a nanosecond laser light source and a picosecond laser light source are each configured to output a plurality of nanosecond pulses and a plurality of picosecond pulses that are focused on a target using one or more concave mirrors or lenses. As an example, at least one of the nanosecond pulsed laser light sources has a different emission wavelength, phase, or both wavelength and phase from one or more of the other nanosecond pulsed laser light sources.

[0111] As an example, the device has variations. As an example, the device is a solid characterized by a central region, a second outer region, a third outer region, and a fourth outer region. Further, the device has two fuel material regions. As an example, the first fuel material region is D (deuterium) T (tritium) Li 6 (lithium) or DTLi 7It is composed of. As an example, the second fuel material region is pB 11 (boron) or pB 10 It is composed of. As an example, the device has three fuel material regions. As an example, the first fuel material region is D (deuterium) T (tritium) Li 6 (lithium) or DTLi 7 It is composed of. As an example, the second fuel material region is DLi 6 or DLi 7 It is composed of. As an example, the third fuel material region is pB 11 or pB 10 It is composed of. As an example, a material different from any of the fuel materials is inserted between pairs of each fuel material region or between any one of the fuel material regions and the ablation material surrounding the device.

[0112] As an example, the device has a conical groove or a metal cone formed through at least the second fuel material region. As an example, the device has a tip of a conical groove or a metal cone disposed near or inside the first fuel material region. As an example, the conical groove or the metal cone is characterized by being more than 1 and less than 10. As an example, the conical groove or the metal cone has a surface coated with a metal having a high Z value selected from at least one of gold (Au), lead (Pb), and other high Z value materials.

[0113] As an example, at least one of the second fuel material region or the third fuel material region contains B x H y or B 10 H 14 borane of.

[0114] As an example, the target device has a pulse width of 1 ns to 40 ns and a total pulse power density of 1×10 13 W / cm 2 ~1×10 18 W / cm 2It is irradiated using a nanosecond pulsed laser and then compressed by at least 100 times to 20,000 times by laser ablation. As an example, the target device is focused on the target device with a spot size of 5 microns to 50 microns, and the total peak pulse power density is 1×10 17 W / cm 2 ~1×10 24 W / cm 2 It is irradiated using a picosecond or femtosecond laser light source that outputs picosecond or femtosecond pulses. As an example, the target device is focused on a conical groove or a metal cone on the target device, and the total peak pulse power density is 1×10 17 W / cm 2 ~1×10 24 W / cm 2 It is irradiated using a picosecond or femtosecond laser light source that outputs picosecond or femtosecond pulses at. As an example, the picosecond laser light source is focused on a conical groove or a metal cone with a small laser spot size of 5 microns to 50 microns. As an example, the picosecond or femtosecond laser light source outputs picosecond or femtosecond pulses while a nanosecond pulsed laser with a pulse width of 1 ns to 40 ns and a total peak pulse power density of 1×10 13 W / cm 2 ~1×10 18 W / cm 2 is irradiating the target device, and is focused on the target device or a conical groove on the target to output picosecond or femtosecond pulses.

[0115] As an example, the target device has a diameter of 1 mm to 9 mm and is also characterized by being spherical. As an example, the target device is cylindrical.

[0116] As an example, the device has a cavity region configured within the vicinity of the central region of the target device. As an example, the device further comprises a conical or cylindrical region configured to reach the cavity region from the outer region through one or more fuel material regions, whereby a picosecond pulse laser characterized by a pulse width of 50 to 500 picoseconds, a total pulse energy of 1 kJ to 500 kJ, and a frequency of 1 to 20 Hz is irradiated onto a part of one or more fuel material regions through the conical or cylindrical region. As an example, the outer region is irradiated by a plurality of nanosecond pulse lasers characterized by a pulse width of 1 ns to 40 ns and a total pulse energy of 1 to 20 MJ, causing at least one compression and implosion of the fuel material region. As an example, the cavity region is characterized by a hot spark in the central region. As an example, the picosecond pulse laser is configured to ablate one of the inner surfaces of the external region in flight that is compressed toward the central region during implosion while being irradiated onto the cavity region, and as a result, the ablated plasma collides in the central region to form a hot spark. As an example, after the hot spark, a deceleration stage is initiated, and the supplied laser energy is converted into the energy of the hot spark through the kinetic energy of the ablation plasma of the outer region in flight. Thereby, it becomes possible to introduce the energy of the hot spark from the energy.

[0117] As an example, the device further includes a picosecond pulse laser configured within the cavity region during the compression process. The timing of introducing this picosecond pulse laser is from immediately after the implosion speed reaches the maximum or almost the maximum to before entering the final stage of compression acceleration where the cavity region still exists in the central region. As an example, the device further comprises a picosecond pulse laser characterized by a pulse width of 50 to 500 picoseconds. As an example, the device further comprises a picosecond pulse laser amplified using an optical enhancement cavity (OEC). As an example, the picosecond pulse laser is configured to go from the outer shell region toward the inner region.

[0118] As an example, the device has a conical or cylindrical region, and the region is composed of a high atomic number material including at least one of gold, lead, titanium, or a composite material. This is to avoid interference by the expanding plasma generated during the implosion process and ensure the path of the picosecond pulsed laser.

[0119] As another example, the present invention provides a fusion fuel target device for inertial confinement fusion (ICF). This device includes a first fuel material region characterized by a first ignition temperature, and a second fuel material region coupled to the first fuel material region. Optionally, this device includes a third fuel material region configured such that the first fuel material region is sandwiched between the second fuel material region and the third fuel material region. The second fuel material is disposed in the central region and has a higher ignition temperature than the first fuel material region. As an example, the third fuel material region is an outer region and has a higher ignition temperature than the first fuel material region.

[0120] As an example, the third fuel material region includes a converter layer that, when colliding with neutrons generated during the fusion reaction, receives the kinetic energy of the neutrons, converts the kinetic energy into the kinetic energy of charged particles, and causes the charged particles to be emitted outward from the central region. As an example, the first fuel material region is configured to ignite earlier than the second fuel material region or the third fuel material region. As an example, the third fuel material region has the characteristics of both a converter and thermonuclear combustion. As an example, the third fuel material region is surrounded by an ablation material that absorbs the incident laser energy and ablates outward to drive the implosion. As an example, the third fuel material region has the characteristics of both a converter and ablation.

[0121] As an example, the first fuel material region includes at least one of D (deuterium), T (tritium), DLi 6 (deuterium-lithium-6), or DTLi 7 (deuterium-lithium-7). As an example, the second fuel material region includes DLi 6(Deuterium Lithium-6) or DLi 7 (Deuterium Lithium-7). As an example, the third fuel material region includes P (or H) B 11 or pB 10 and includes at least one of them. As an example, the third fuel material region includes (Hydrogen) H, P (or H)-B 11 or pB 10 or at least one of low atomic number particles.

[0122] As an example, the device is irradiated with a plurality of nanosecond pulsed lasers with a pulse width of 1 ns to 40 ns and a total pulse power density of 1×10 13 W / cm 2 ~1×10 20 W / cm 2 and these plurality of nanosecond pulsed lasers compress the device by at least 100 times to 20,000 times simultaneously with the thermonuclear combustion initiated in the first fuel material region. As an example, the device is characterized by the thermonuclear combustion in the first fuel material region, and this combustion is initiated by picosecond or femtosecond lasers from outside the device. The picosecond or femtosecond lasers are irradiated with a total peak laser power density of 1×10 17 W / cm 2 ~1×10 24 W / cm 2 while being irradiated simultaneously with nanosecond pulsed lasers with a pulse width of 1 ns to 40 ns and a total pulse power density of 1×10 13 W / cm 2 ~1×10 18 W / cm 2 .

[0123] As an example, the device further comprises a conical groove or a metal cone configured within the device. As an example, the conical groove or the metal cone comprises a tip portion disposed near or inside the first fuel material region. As an example, the conical groove or the metal cone comprises an outer surface, and the outer surface is coated with a high-Z value metal material, and the metal material is at least one of gold (Au), lead (Pb), and other suitable high-Z metal materials. As an example, a picosecond laser or a femtosecond laser is irradiated through the conical groove configured in the device. As an example, the picosecond laser is configured to be focused on the conical groove or the metal cone configured on the device with a laser spot size of 5 microns to 50 microns.

[0124] As an example, the device has a cavity region configured within the vicinity of the central region of the device. A conical or cylindrical region is configured to extend from the outer shell region through one or more fuel material regions to the cavity region. With this structure, a picosecond pulsed laser with a pulse width of 50 to 500 picoseconds, a total pulse energy of 1 kJ to 500 kJ, and a frequency of 1 to 20 Hz is irradiated through the conical or cylindrical region onto a part of one or more fuel material regions.

[0125] As an example, the device is characterized in that its shape is spherical with a diameter of 1 mm to 10 mm. As an example, the device further comprises a material different from any of the first fuel material region, the second fuel material region, and the third fuel material region (collectively referred to as the fuel material regions), and this material is configured to be disposed between at least a pair of the fuel material regions, or between any of the fuel material regions and the ablation material.

[0126] In the above-described technology shown in the figure, no matter what kind of material is inserted between each fusion material region or between the fusion material region and the ablation material, since these inserted materials do not change the concept of the present invention, they are considered to be included in this technology.

[0127] In the above-described technology shown in the figure, the irradiation timing between the picosecond or femtosecond laser light source and the nanosecond pulse laser light source is as follows. The picosecond or femtosecond laser light source outputs picosecond or femtosecond pulses condensed on the metal cone and the conical groove on the target at a total peak pulse power density of 1×10 20 W / cm 2 ~1×10 24 W / cm 2 On the other hand, a nanosecond pulse laser with a pulse width of 1 ns to 40 ns and a total pulse power density of 1×10 13 W / cm 2 ~1×10 18 W / cm 2 irradiates the target, and then the target is compressed by at least 100 times to 20,000 times by laser ablation.

[0128] In this technology, the picosecond pulse laser light source refers to the laser source having a pulse width of 1 picosecond to 900 picoseconds. The nanosecond pulse laser light source refers to the laser source having a pulse width of 1 nanosecond to 40 nanoseconds. The femtosecond pulse laser light source refers to the laser source having a pulse width of 10 femtoseconds to 1000 femtoseconds. The wavelengths of the nanosecond, picosecond, and femtosecond laser light sources range from UV (350 nm) to IR (1060 nm).

[0129] As an example, the device is a solid characterized by a first fuel material region, a second fuel material region, and a third fuel material region. As an example, the target device is a solid at room temperature. As an example, the melting point of HLi is 692°C. DLi and DTLi are considered to have similar melting points. pB 11 used as B 10 H 14 borane has a melting point of 100°C. As an example, borane is coated with a polymer to prevent the evaporation of toxic substances from borane. As an example, the melting point of the polymer is in the range of 50 to 100°C depending on the type of material. Therefore, a solid, as an example, means that the target is in a solid state at a temperature of at least 10 to 50°C.

[0130] Of course, other variations, alternatives, and modifications may exist.

[0131] The above is a complete description of specific embodiments, but various variations, alternative structures, and equivalents can be used. As an example, a high-intensity laser forms a resonator between a pair of mirror devices to cause ignition of a fuel pellet by utilizing the constructive interference of each laser beam. As an example, a first path by a high-intensity pulsed laser is provided within a resonator device. As an example, the present invention provides a system and method for generating a concentric or spherical resonator within a reaction region to focus laser light at the center of a reactor. Further, terms such as "first," "second," "third," and "final" do not imply an order in any of the present embodiments. Various numerical limitations in another example may not be limited in some examples. Further, the target of the present invention can also be used for other applications. Therefore, the above description and illustration do not limit the scope of the present invention, and the scope of the present invention is defined by the appended claims.

Claims

1. 1. A fusion fuel target device for inertial confinement fusion (ICF), comprising: a first fuel material region characterized by a first ignition temperature; a second fuel material region coupled to the first fuel material region; and optionally, a third fuel material region, the third fuel material region being configured such that the first fuel material region is sandwiched between the second fuel material region and the third fuel material region; Equipped with the second fuel material is configured in a central region and has a higher ignition temperature than the first fuel material region; the third fuel material region is an outer region and has a higher ignition temperature than the first fuel material region. Fusion fuel targeting device.

2. The third fuel material region is characterized by both converter and thermonuclear combustion. The device of claim 1 .

3. the third fuel material region is surrounded by an ablative material that absorbs incident laser energy and ablates it outward to drive the implosion; The device of claim 1 .

4. the third fuel material region being characterized as both a converter and an ablator; The device of claim 1 .

5. The first fuel material region is composed of D (deuterium), T (tritium), DHe ３ , DD, or DLi ６ (Deuterium-Lithium-6), or DLi ７ (deuterium-lithium-7), The device of claim 1 .

6. The second fuel material region is DHe ３ , DLi ６ (Lithium deuterium ６ ), DLi ７ (Lithium deuterium ７ ), H (hydrogen) Li ６ , H.L.I. ７ , pB 11 , or P.B. 10 At least one of: The device of claim 1 .

7. The third fuel material region is P(or H)B 11 or pB 10 At least one of: The device of claim 1 .

8. The third fuel material region is (hydrogen)H, P(or H)-B 11 or pB 10 or low atomic number particles; The device of claim 1 .

9. and further comprising a conical groove configured within the device. The device of claim 1 .

10. the conical groove includes a tip configured adjacent or within the first fuel material region. The device of claim 9.

11. the conical groove has an outer surface, the outer surface being coated with a high-Z metallic material, the metallic material including at least one of gold (Au), lead (Pb), and other suitable high-Z metallic materials; The device of claim 9.

12. The device is spherical in shape with a diameter ranging from 1 mm to 10 mm. The device of claim 1 .

13. the ablation material is disposed between at least one of the first fuel material region, the second fuel material region, and the third fuel material region (collectively, fuel material regions); and the ablation material is disposed between at least one of the fuel material regions and the ablation material. The device of claim 1 .

14. a cavity is formed in a central region of the second fuel material region; The device of claim 1 .

15. The device is characterized in that it is a solid state. The device of claim 1 .

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