A magnetic field guiding based laser fusion fast ignition high efficiency heating system and method

Abstract

The application belongs to the technical field of nuclear power generation, and particularly relates to a laser fusion fast ignition high-efficiency heating system and method based on magnetic field guidance. The laser fusion fast ignition high-efficiency heating method based on magnetic field guidance comprises the following steps: 1) generating a guiding magnetic field by using electromagnetism; 2) forming a high-energy charged particle beam by using a picosecond laser to interact with a heating gold cone and / or other substances; and 3) heating the compressed thermonuclear fuel under the guiding action of the guiding magnetic field obtained in step 1) and the heating gold cone by using the high-energy charged particle beam obtained in step 2). The high-energy charged particle beam is constrained and collimated by using the guiding magnetic field, so that the laser energy is deposited in the thermonuclear fuel as much as possible, the conversion efficiency of the picosecond laser energy to the energy in a hot spot is significantly improved, and the application requirement of the laser fusion energy is met.

Description

Technical Field

[0001] This invention belongs to the field of nuclear power generation technology, and in particular relates to a high-efficiency heating system and method for laser fusion fast ignition based on magnetic field guidance. Background Technology

[0002] In the 1960s, Nachos of the United States and Academician Wang Ganchang of my country independently proposed the concept of using lasers to achieve nuclear fusion. In 2022, the U.S. National Ignition Facility, employing an indirect-drive center ignition technology, achieved for the first time in human history an output energy greater than the laser input energy, successfully verifying the scientific feasibility of laser-controlled nuclear fusion. However, the laser-indirect-drive center ignition technology it used has certain inherent physical difficulties, including low energy utilization efficiency and strong instability of the implosion fluid, making it difficult to meet the high-gain requirements of commercial fusion energy.

[0003] In 2018, after carefully analyzing decades of research progress in laser fusion, Chinese scientist Academician Zhang Jie proposed the Dicone-in-Cone (DCI) ignition scheme, building upon his original 1997 shell-in-cone idea. This scheme combines the advantages of direct-drive technology with fast ignition technology, further improving compression efficiency while separating the compression and heating ignition processes of thermonuclear fuel. This allows for precise control of the entire fusion compression and ignition process, achieving high-gain fusion ignition with relatively low laser energy. This scheme holds immense promise for low-cost, high-gain, and high-efficiency controlled nuclear fusion power generation; however, how to achieve rapid heating of the compressed fuel remains an open question worthy of further research. Summary of the Invention

[0004] In view of the shortcomings of the prior art, the present invention provides a high-efficiency heating system and method for laser fusion fast ignition based on magnetic field guidance, which is used to solve the defects of existing fast ignition schemes in terms of energy transfer efficiency, fast electron orientation control and energy deposition localization in the process of achieving rapid heating of compressed fuel.

[0005] This invention provides a method for efficient heating in laser fusion based on magnetic field-guided rapid ignition, the method comprising:

[0006] 1) Using electromagnetic methods to generate a guiding magnetic field;

[0007] 2) A high-energy charged particle beam is formed by the interaction of a picosecond laser with a heated gold cone and / or other materials;

[0008] 3) The high-energy charged particle beam obtained in step 2) heats the compressed thermonuclear fuel under the guidance of the guiding magnetic field and the heating gold cone obtained in step 1).

[0009] In some embodiments of the present invention, the electromagnetic means described in step 1) is one or more of the following: the interaction between a nanosecond laser and a capacitor coil target, the compression and amplification of a pulsed strong magnetic field using the magnetic freezing effect, or the inverse Faraday effect.

[0010] In some embodiments of the present invention, the guiding magnetic field in step 1) is along the heating direction and covers the transport region of the high-energy charged particle beam; the magnetic induction intensity of the guiding magnetic field is ≥1000 Tesla; the duration of the guiding magnetic field is ≥10 picoseconds; and the radius of the region where the guiding magnetic field exists is 30-100 micrometers.

[0011] In some embodiments of the present invention, the total energy of the picosecond laser in step 2) is ≥20,000 joules; the peak laser intensity of the picosecond laser is ≥1 x 10⁻⁶. 20 Watts per square centimeter; the laser pulse duration of the picosecond laser is 3-20 picoseconds; the laser spot diameter of the picosecond laser is ≤50 micrometers.

[0012] In some embodiments of the present invention, the charged particles in the high-energy charged particle beam in step 2) are selected from one or more of fast electrons, protons, or heavy ions.

[0013] In some embodiments of the present invention, the other substances mentioned in step 2) are selected from one or more of metal thin films, crystal thin films, and polymer thin films.

[0014] In some embodiments of the present invention, the opening angle of the heating gold cone in step 3) is 50-80°; the bottom of the heating gold cone is sealed, and the bottom radius is 10-30 micrometers.

[0015] In some embodiments of the present invention, the distance between the heated gold cone and the compressed thermonuclear fuel in step 3) is 30-100 micrometers.

[0016] In some embodiments of the present invention, step 3) involves heating to 5-12 kiloelectron volts.

[0017] This invention also provides a high-efficiency heating system for rapid ignition of laser fusion based on magnetic field guidance, comprising:

[0018] A nanosecond laser source and a capacitor coil target are used to generate a guiding magnetic field that covers the high-energy charged particle beam transport region along the heating direction.

[0019] A picosecond laser source and a heated gold cone are used. The picosecond laser beam emitted from the picosecond laser source is targeted to the heated gold cone and interacts with the heated gold cone and / or other materials to form a high-energy charged particle beam. Under the guidance of the heated gold cone and the guiding magnetic field, the compressed thermonuclear fuel is targeted for heating. The other materials are located inside the heated gold cone.

[0020] The present invention has the following beneficial effects:

[0021] This invention utilizes a guiding magnetic field along the heating direction (from the high-energy charged particle beam to the thermonuclear fuel) that covers the transport region of the high-energy charged particle beam, guiding it to achieve concentrated and directional transport. This maximizes the deposition of its energy into the compressed, high-density thermonuclear fuel, achieving highly efficient heating. Simultaneously, the use of a high-energy nanosecond laser, a high-intensity magnetic field generated by a capacitor coil target or other electromagnetic means, and the auxiliary guidance of a heated gold cone further improves the directionality of the high-energy charged particle beam, reduces its divergence angle, and significantly enhances the conversion efficiency from picosecond laser energy to the hot spot energy. The energy conversion efficiency can reach 10%-20% (compared to <5% for existing heating methods, generally around 1%), meeting the future application requirements of laser fusion energy. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the high-efficiency fast electron ignition heating principle guided by a magnetic field in Embodiment 1 of the present invention.

[0023] Figure 2 This is a schematic diagram of the transport of a high-energy charged particle beam under the influence of a guiding magnetic field in Embodiment 1 of the present invention.

[0024] Figure 3 This is a schematic diagram showing the temperature and density of thermonuclear fuel after being heated by a high-energy charged particle beam in Embodiment 1 of the present invention.

[0025] Component designation explanation

[0026] 1 Nanosecond laser source

[0027] 2. Capacitor coil target

[0028] 3 Picosecond laser source

[0029] 4. Heating the gold cone

[0030] 5. Compressed thermonuclear fuel Detailed Implementation

[0031] The following details the implementation of the highly efficient heating system and method for the magnetic field-guided laser fusion fast ignition scheme.

[0032] This invention utilizes a guiding magnetic field along the heating direction, covering the transport region of the high-energy charged particle beam, to guide the beam, achieving concentrated and directional electron transport. This allows the beam to deposit as much energy as possible into the compressed, high-density thermonuclear fuel, achieving highly efficient heating. Furthermore, a heating gold cone can be used to further guide the high-energy charged particle beam. The conversion efficiency of the heated picosecond laser energy to the fuel's internal energy is 10%-20%, meeting the future application requirements of laser fusion energy. Based on this, this invention was completed.

[0033] Please see Figures 1-3 It should be understood that the structures, proportions, sizes, etc., illustrated in the accompanying drawings are merely for illustrative purposes to aid those skilled in the art and to facilitate understanding and reading. They are not intended to limit the scope of the invention and therefore have no substantial technical significance. Any modifications to the structure, changes in proportions, or adjustments to size, without affecting the effectiveness and purpose of the invention, should still fall within the scope of the technical content disclosed in this invention. Furthermore, the terms such as "upper," "lower," "left," "right," "middle," and "one" used in this specification are merely for clarity and not intended to limit the scope of the invention. Changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered within the scope of the invention's implementation.

[0034] This invention provides a method for rapid ignition and efficient heating of laser fusion based on magnetic field guidance, the method comprising:

[0035] 1) Using electromagnetic methods to generate a guiding magnetic field;

[0036] 2) A high-energy charged particle beam is formed by the interaction of a picosecond laser with a heated gold cone and / or other materials;

[0037] 3) The high-energy charged particle beam obtained in step 2) heats the compressed thermonuclear fuel under the guidance of the guiding magnetic field and the heating gold cone obtained in step 1).

[0038] In the magnetic field-guided laser fusion fast ignition high-efficiency heating method provided by this invention, "fast ignition" is a technical term in the field of fusion research. The fusion technology route of this invention is fast ignition, specifically referring to igniting compressed high-density fusion fuel using a high-energy laser or other external energy source to achieve inertial confinement fusion. In the magnetic field-guided laser fusion fast ignition high-efficiency heating method provided by this invention, the electromagnetic means mentioned in step 1) are one of the following: the interaction between a nanosecond laser and a capacitor coil target, a pulsed strong magnetic field compressed and amplified by the magnetic freezing effect, or the inverse Faraday effect. In a specific embodiment, a guiding magnetic field is generated by the interaction between a nanosecond laser and a capacitor coil target, wherein the energy of the nanosecond laser is 2 kilojoules, the pulse width is 1 nanosecond, and the wavelength is 1054 nanometers.

[0039] In the magnetic field-guided laser fusion fast ignition high-efficiency heating method provided by this invention, the nanosecond laser interacts with the capacitor coil target to generate a guiding magnetic field. Specifically, when the nanosecond laser pulse irradiates the capacitor coil target, the laser energy rapidly heats the target surface, generating a large amount of thermal plasma. Since the electron velocity is much greater than that of ions, the emitted hot electrons are first captured by the front target disk, making them negatively charged, while simultaneously making the rear target disk positively charged. The potential difference between the two target disks drives a strong current in the metal coil, and correspondingly generates a strong magnetic field. The duration of the magnetic field is several nanoseconds.

[0040] The specific process for generating the pulsed strong magnetic field compressed and amplified by the magnetofreezing effect is as follows: First, a pulsed strong magnetic field is generated through a pulsed power supply and a pulsed magnet. At this time, the magnetic induction intensity is tens of Tesla, and the duration can reach the millisecond scale. After this magnetic field enters the uncompressed thermonuclear fuel, the thermonuclear fuel is compressed. At this time, due to the magnetofreezing effect of the magnetohydrodynamics, the magnetic field will be further compressed and amplified to achieve a magnetic field on the order of kilotas. The time scale of the compression and amplification process is several nanoseconds.

[0041] The inverse Faraday effect refers to the magnetic field generated by the interaction of a circularly polarized high-intensity pulsed laser with a low-density plasma. The electric field of the circularly polarized electromagnetic wave can induce a current, which, according to Maxwell's equations, will produce a static magnetic field.

[0042] In the high-efficiency heating method for rapid ignition of laser fusion based on magnetic field guidance provided by this invention, the guiding magnetic field in step 1) refers to a magnetic field within a specific spatial region that guides charged particles to move along a predetermined path by controlling the direction and intensity of the magnetic field. Its main functions include controlling particle trajectories, focusing the particle beam, and stabilizing particle motion. In a specific embodiment of this invention, the guiding magnetic field covers the transport region of the high-energy charged particle beam along the heating direction; the magnetic induction intensity of the guiding magnetic field is ≥1000 Tesla. If the magnetic induction intensity is lower than this range, it cannot generate sufficient lateral confinement effect on the high-energy charged particle beam, causing some high-energy electrons to fail to enter the high-density thermonuclear fuel, resulting in a decrease in heating efficiency. The duration of the guiding magnetic field is ≥10 picoseconds; the radius of the area where the guiding magnetic field exists is 30-100 micrometers, optionally 30-50 micrometers, 50-80 micrometers, or 80-100 micrometers, preferably 30 micrometers, 50 micrometers, or 100 micrometers.

[0043] In the magnetic field-guided laser fusion fast ignition and high-efficiency heating method provided by this invention, the total energy of the picosecond laser in step 2) is ≥20,000 joules; the peak laser intensity of the picosecond laser is ≥1 x 10⁻⁶. 20 The picosecond laser pulse duration is 3-20 picoseconds, optionally 3-10 picoseconds, 10-12 picoseconds, 12-16 picoseconds, 16-20 picoseconds, or 10-20 picoseconds, preferably 10 picoseconds; the diameter of the picosecond laser focal spot is ≤50 micrometers. Picosecond laser parameters inferior to the aforementioned range will prevent the thermonuclear fuel from being heated to the fusion ignition temperature.

[0044] In the magnetic field-guided laser fusion fast ignition high-efficiency heating method provided by this invention, the charged particles in the high-energy charged particle beam in step 2) are selected from one or more of fast electrons, protons, or heavy ions. When the charged particles in the high-energy charged particle beam are fast electrons (i.e., electrons with high kinetic energy), the total energy of the high-energy charged particle beam is ≥10,000 joules, the beam spot diameter is ≤50 micrometers, and the beam divergence angle is ≤50 degrees. In a specific embodiment of this invention, the picosecond laser in step 2) interacts with the heated gold cone (heated gold cone base) to generate fast electrons; when the picosecond laser interacts with other materials (such as metal thin films, crystal thin films, or polymer thin films), protons or heavy ions are generated in addition to fast electrons.

[0045] In the magnetic field-guided laser fusion fast ignition high-efficiency heating method provided by this invention, the other substances mentioned in step 2) are selected from one or more of metal thin films, crystal thin films, and polymer thin films. The metal in the metal thin film can be, for example, gold, copper, aluminum, silver, or titanium; the crystal in the crystal thin film can be, for example, diamond, graphene, silicon carbide, or gallium nitride; and the polymer in the polymer thin film can be, for example, polyethylene, polypropylene, polystyrene, or polyethylene terephthalate. The thickness of the thin film varies depending on the particle type and physical mechanism; for example, the thickness of a metal or crystal thin film can be 5-30 nanometers, while the thickness of a metal or polymer thin film can be 1-100 micrometers. In a specific embodiment of this invention, the other substances are disposed inside the heating gold cone.

[0046] In the magnetic field-guided laser fusion fast ignition high-efficiency heating method provided by this invention, the compressed thermonuclear material mentioned in step 3) refers to a fusion material with high density after compression by laser or other methods. This material can generate a nuclear fusion reaction under high temperature and high pressure, releasing a large amount of energy. In a specific embodiment of this invention, the areal density of the compressed thermonuclear material is ≥0.6 g / cm², the density is ≥200 g / cm³, and the fuel composition is deuterium-tritium, deuterium-deuterium, carbon-deuterium, etc.

[0047] In the magnetic field-guided laser fusion fast ignition high-efficiency heating method provided by this invention, the main function of the heated gold cone in step 3) is to heat the surface of the gold cone with laser during the experiment to generate a high-energy-density physical effect. Its unique conical design helps to concentrate energy, thereby achieving efficient energy transfer and heating effect. In a specific embodiment of this invention, when the picosecond laser interacts only with the heated gold cone, the heated gold cone can act as "matter," generating fast electrons with the picosecond laser and subsequently providing auxiliary guidance for the fast electrons. That is, the heated gold cone simultaneously participates in the roles of "acting matter" and "auxiliary guidance." When the picosecond laser interacts with other matter, such as metal thin films, crystal thin films, or polymer thin films, it can generate protons or heavy ions other than fast electrons. In this case, the other matter only plays the role of "matter" that interacts with the picosecond laser to generate a high-energy particle beam, and the heated gold cone only plays an auxiliary guiding role.

[0048] In the magnetic field-guided laser fusion fast ignition high-efficiency heating method provided by this invention, the opening angle of the heating gold cone in step 3), i.e., the cone angle of the heating gold cone, is 50-80°, for example, 50-60°, 60-70°, or 70-80°, preferably 50°, 60°, or 70°. Within this range, the opening angle of the heating gold cone can effectively concentrate and guide the direction of the high-energy charged particle beam, ensuring that the high-energy charged particle beam is not easily scattered when passing through the heating process, maintaining efficient energy transport. The bottom of the heating gold cone, i.e., the end closest to the thermonuclear fuel, is sealed, and the bottom radius is 10-30 micrometers, optionally 10 micrometers or 20 micrometers. This design can further focus the high-energy charged particle beam, making it more concentrated in the compressed thermonuclear fuel, which helps to form a denser hot spot and improve heating efficiency.

[0049] In the magnetic field-guided laser fusion fast ignition high-efficiency heating method provided by this invention, the distance between the bottom of the heated gold cone and the center of the compressed thermonuclear fuel in step 3) is 30-100 micrometers, which can be selected as 30-50, 50-70, 70-80, 80-100, 50-80, or 30-80 micrometers, etc., preferably 30 micrometers, 50 micrometers, or 80 micrometers. If the distance is too close, the gold cone will be destroyed by the compressed fuel; if it is too far, the heating efficiency will decrease.

[0050] In the magnetic field-guided laser fusion fast ignition and efficient heating method provided by this invention, step 3) involves the high-energy charged particle beam depositing energy in the compressed thermonuclear fuel, converting picosecond laser energy into hot spot energy. The thermonuclear fuel is heated to the fusion temperature within 3-20 picoseconds, preferably 3-10 picoseconds, 10-15 picoseconds, 15-20 picoseconds, or 10-20 picoseconds, with 10 picoseconds being preferred. The fuel is then heated to 5-12 kiloelectron volts (i.e., 58.02 million to 139 million °C), preferably 5-8 kiloelectron volts, 8-10 kiloelectron volts, 5-10 kiloelectron volts, or 10-12 kiloelectron volts, with 10 kiloelectron volts being preferred, to meet the temperature requirements of the fusion reaction. Once the desired fusion reaction temperature is reached, the compressed fuel undergoes a fusion reaction, releasing a large amount of energy.

[0051] The "high efficiency" in the magnetic field-guided laser fusion fast ignition high-efficiency heating method provided by this invention specifically refers to a high energy conversion efficiency from picosecond laser energy to hot spot internal energy. This energy conversion efficiency can be directly obtained from the mathematical algorithms and models executed by the computer during numerical simulation. The specific formula is: Energy conversion efficiency = Increased hot spot internal energy / Picosecond laser energy. In specific embodiments of this invention, the heating method can achieve an energy conversion efficiency of 10-20% from picosecond laser energy to hot spot internal energy, optionally 10-12%, 12-14%, 14-16%, 16-17%, 17-19%, 19-20%, 16-19%, or 10-19%, preferably 10%, 15%, or 20%. Existing heating methods generally have an energy conversion efficiency of <5%, typically around 1%. Therefore, this invention significantly improves the energy conversion efficiency of the heating method, meeting the application requirements of laser fusion energy.

[0052] This invention provides a high-efficiency heating system for rapid ignition of laser fusion based on a magnetic field-guided process, such as... Figure 1 As shown, it includes:

[0053] A nanosecond laser source 1 and a capacitor coil target 2 are provided. The nanosecond laser source 1 is directly facing the capacitor coil target 2 to ensure that the nanosecond laser beam is incident perpendicularly on the capacitor coil target 2. The nanosecond laser beam emitted from the nanosecond laser source 1 is focused on the capacitor coil target 2 to provide a guiding magnetic field along the heating direction and covering the transport region of the high-energy charged particle beam.

[0054] The picosecond laser source 3 and the heating gold cone 4 are positioned directly opposite each other to ensure that the entire picosecond laser beam enters the interior of the heating gold cone 4. The picosecond laser beam emitted from the picosecond laser source 3 targets the heating gold cone 4 and interacts with the heating gold cone 4 and / or other materials to form a high-energy charged particle beam. Under the guidance of the heating gold cone 4 and the guiding magnetic field, the beam targets and heats the compressed thermonuclear fuel 5. The other materials are located inside the heating gold cone 4.

[0055] The heated gold cone 4 is positioned within the guiding magnetic field generated by the interaction of the nanosecond laser source 1 and the capacitor coil target 2. The heated gold cone 4 only needs to be positioned within the guiding magnetic field, and the direction of the generated charged particle beam must be parallel to the magnetic field direction. There are no special requirements regarding its orientation or distance; for example, the heated gold cone 4 can be positioned in one of the four cardinal directions (up, down, left, right) of the nanosecond laser source 1 and the capacitor coil target 2. In practice, the distance between the heated gold cone 4 and the nanosecond laser source 1 and the capacitor coil target 2 can be adjusted according to the size of the experimental site and the volume of the device used to emit the nanosecond or picosecond laser.

[0056] Working principle of the invention:

[0057] First, a high-intensity guiding magnetic field covering the fast electron transport region is generated along the heating direction using nanosecond lasers interacting with a capacitor coil target or other electromagnetic means. Subsequently, a high-energy, high-power picosecond laser interacts with a heated gold cone and / or other materials to generate a high-energy charged particle beam. This beam is then directionally transported to the compressed thermonuclear fuel under the guidance of the guiding magnetic field and the heated gold cone. Due to the guiding magnetic field, the divergence angle of the high-energy charged particle beam is reduced, allowing more charged particles to be transported to the high-density region and deposited into the thermonuclear fuel, thus achieving a more energy-efficient charged particle heating process and forming hot spots. Simultaneously, using a heated gold cone to further guide the high-energy charged particle beam can further improve the directionality of the charged particles.

[0058] To make the technical means, creative features, objectives and effects of this invention easy to understand, the invention will be specifically described below in conjunction with embodiments and accompanying drawings.

[0059] Example 1

[0060] High-efficiency heating method for rapid ignition of laser fusion based on magnetic field guidance

[0061] like Figure 1 As shown, a high-intensity guiding magnetic field is first generated by the interaction of a nanosecond laser with a capacitor coil target. This guiding magnetic field covers both the high-energy charged particle beam transport region and the fast electron transport region along the heating direction. The magnetic induction intensity of the guiding magnetic field is 1000 Tesla; the duration of the guiding magnetic field is 100 picoseconds; and the radius of the region where the guiding magnetic field exists is 50 micrometers. Subsequently, a high-energy charged particle beam generated by the interaction of a high-energy, high-power picosecond laser with the bottom of a gold cone is directionally transported to the compressed high-density thermonuclear fuel under the influence of the guiding magnetic field. The total energy of the picosecond is 40,000 joules; the peak laser intensity is 3.9 x 10⁻⁶. 20 The laser pulse duration is 10 picoseconds per square centimeter; the laser focal spot diameter is 30 micrometers. Simultaneously, an additional heated gold cone is used to assist in guiding fast electrons, further improving the directionality of the high-energy charged particle beam. The heated gold cone has an opening angle of 50 degrees, a sealed bottom, and a bottom radius of 15 micrometers. With magnetic field guidance, the conversion efficiency from picosecond laser energy to the internal energy of the hot spot can reach 17%.

[0062] A schematic diagram of the transport of a high-energy charged particle beam under the influence of a guiding magnetic field is shown below. Figure 2As shown, the first row of images illustrates the density distribution of high-density thermonuclear fuel, while the second row shows the equivalent current of fast electron transport. With the application of a guiding magnetic field, the fast electrons move in a spiral motion along the magnetic field lines, thus significantly improving their directionality. It is clearly visible in the images that without a magnetic field, the fast electron distribution is relatively dispersed, and the incident depth is shallow. After applying a 2,000 Tesla magnetic field along the heating direction, covering the transport region of the high-energy charged particle beam, the fast electron current is significantly enhanced and exhibits excellent directionality.

[0063] A schematic diagram showing the temperature and density of thermonuclear fuel heated by a high-energy charged particle beam is shown below. Figure 3 As shown, in Example 1, the fast electrons generated by the 40,000 joules picosecond laser energy within 10 picoseconds are transported to the compressed high-density thermonuclear fuel under the guidance of a magnetic field, depositing energy in the fuel and rapidly heating it to an ultra-high temperature of 10 kiloelectron volts, or 116 million °C, meeting the temperature requirements for fusion reaction. In the subsequent fusion reaction, 10 million joules of fusion energy are released. In Example 1, the conversion efficiency from picosecond laser energy to the hot spot energy is as high as 17%.

[0064] Example 2

[0065] The heating method is basically the same as in Example 1, except that the total energy of the picosecond laser is changed to 30,000 joules. In this Example 2, the conversion efficiency of picosecond laser energy to hot spot energy is 16%.

[0066] Example 3

[0067] The heating method is basically the same as in Example 1, except that the total energy of the picosecond laser is changed to 50,000 joules. In this Example 3, the conversion efficiency of picosecond laser energy to hot spot energy is 19%.

[0068] Example 4

[0069] The heating method is basically the same as in Example 1, except that the total energy of the picosecond laser is changed to 20,000 joules. In this Example 4, the conversion efficiency of picosecond laser energy to hot spot energy is 10%.

[0070] Comparative Example 1

[0071] The heating method is basically the same as in Example 1, except that the total energy of the picosecond laser is changed to 10,000 joules. In this comparative example 1, the conversion efficiency of picosecond laser energy to hot spot energy is only 6%.

[0072] The above embodiments are for illustrating the implementation schemes disclosed in this invention and should not be construed as limiting the invention. Furthermore, various modifications and variations of the methods listed herein will be apparent to those skilled in the art without departing from the scope and spirit of the invention. Although the invention has been specifically described in conjunction with various specific preferred embodiments, it should be understood that the invention should not be limited to these specific embodiments. In fact, various modifications as described above that are obvious to those skilled in the art to obtain the invention should be included within the scope of this invention.

Claims

1. A high-efficiency heating method for rapid ignition of laser fusion based on magnetic field guidance, characterized in that, The method includes: 1) A guiding magnetic field is generated by compressing and amplifying a pulsed strong magnetic field using the magnetic freezing effect; specifically, this includes: first, the pulsed strong magnetic field is introduced into the uncompressed thermonuclear fuel, and then the thermonuclear fuel is compressed. The magnetic freezing effect of the magnetohydrodynamics is used to compress and amplify the pulsed strong magnetic field along with the compression of the thermonuclear fuel, forming a guiding magnetic field on the order of kilotas; the guiding magnetic field is along the heating direction, covers the transport region of the high-energy charged particle beam, the magnetic induction intensity of the guiding magnetic field is ≥1000 Tesla, the duration of the guiding magnetic field is ≥10 picoseconds, and the radius of the region where the guiding magnetic field exists is 30-100 micrometers; 2) A high-energy charged particle beam is formed by the interaction of a picosecond laser with other materials inside a heated gold cone. The charged particles in the high-energy charged particle beam are protons or heavy ions, and the other materials are selected from one or more of metal thin films, crystal thin films, and polymer thin films. The heated gold cone is located within the guiding magnetic field. The total energy of the picosecond laser is not less than 20,000 joules, and the peak laser intensity of the picosecond laser is not less than 1 × 10². 0 The laser pulse duration of the picosecond laser is 3-20 picoseconds, and the laser spot diameter of the picosecond laser is no greater than 50 micrometers. 3) The high-energy charged particle beam obtained in step 2) heats the compressed thermonuclear fuel under the guidance of the guiding magnetic field obtained in step 1) and the guiding action of the heating gold cone; the opening angle of the heating gold cone is 50-80°, the bottom of the heating gold cone is sealed, and the bottom radius is 10-30 micrometers; the distance between the bottom of the heating gold cone and the center of the compressed thermonuclear fuel is 30-100 micrometers; the high-energy charged particle beam heats the compressed thermonuclear fuel to 5-12 kiloelectron volts within 3-20 picoseconds.

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