Laser transverse phase shaping system and vortex light generating device

Abstract

The invention relates to a laser transverse phase shaping system and a vortex light generating device.The laser transverse phase shaping system comprises a wavefront inclined reflecting device and a first concave reflecting mirror which are sequentially arranged in the laser transmission direction and located on the same vertical plane; the wavefront inclined reflection device is used for shaping the transverse phase of incident laser to obtain shaped laser and transmitting the shaped laser to the first concave reflector; and the first concave reflector is used for converging the shaped laser so as to obtain the converged shaped laser.

Description

Technical Field

[0001] The present invention relates to the technical field of laser light sources, and more specifically to a laser transverse phase shaping system and a vortex light generating device. Background Art

[0002] Vortex light is a light beam with orbital angular momentum that has a spiral wavefront during transmission. It has important applications in laser detection, optical communications, and quantum optics, and has broad application prospects in the short-wavelength field. Since vortex light generation is currently concentrated in the infrared to ultraviolet band, it is difficult to generate high-power vortex light in the X-ray band using existing conventional optical methods and high-harmonic amplification technology. In recent years, with the continuous research and development of accelerator light sources, X-ray vortex light has also been widely used. However, the current vortex light generation method based on accelerator light sources is still difficult to achieve the level of short-wavelength X-rays.

[0003] At present, the generation of high-power, high-coherence, X-ray vortex light has gradually become an important development direction in the field of photon science. Among them, free electron lasers and transverse phase shaping seed lasers can generate high-power coherent vortex light in the infrared to ultraviolet bands. However, due to the short wavelength of X-rays, which is less than ten nanometers, existing methods cannot achieve structural control of short-wavelength pulses in terms of precision, and therefore cannot obtain short-wavelength X-ray radiation pulses with specific structures under high coherence and high energy conditions.

[0004] Therefore, how to obtain high-power coherent vortex light with short wavelength is a problem that technicians in this field need to solve urgently. Summary of the invention

[0005] The object of the present invention is to provide a laser transverse phase shaping system and a vortex light generating device to generate high-power and high-coherence short-wavelength vortex free electron laser pulses in the X-ray band.

[0006] Based on the above purpose, on one hand, the present invention provides a laser transverse phase shaping system, including a wavefront tilt reflection device and a first concave reflection mirror, wherein the wavefront tilt reflection device and the first concave reflection mirror are arranged in sequence along the laser transmission direction and are located in the same vertical plane, the wavefront tilt reflection device is used to shape the transverse phase of the incident laser to obtain a shaped laser, and transmit the shaped laser to the first concave reflection mirror; the first concave reflection mirror is used to converge the shaped laser to obtain a converged shaped laser.

[0007] Furthermore, the wavefront tilt reflection device includes a first reflection plate, a second reflection plate and a rotation axis, the first reflection plate and the second reflection plate are connected to the rotation axis and can rotate around the rotation axis independently; the incident laser is incident on the first reflection plate and the second reflection plate.

[0008] Further, the first reflecting plate and the second reflecting plate are configured to change the incident angle of the incident laser on the first reflecting plate and the second reflecting plate by rotating around the rotation axis, so as to change the phase of the incident laser at the same lateral position.

[0009] Furthermore, the first reflector, the second reflector and the first concave reflector are all provided with a reflective coating layer.

[0010] The laser transverse phase shaping system of the present invention can adjust the transverse phase structure of the incident laser through a wavefront tilt reflection device to obtain a shaped laser, and the first concave reflection mirror converges the shaped laser and changes its propagation direction, thereby generating a high-power transverse phase shaping laser with a controllable transverse phase structure; by changing the inclination angles of the first reflection plate and the second reflection plate of the wavefront tilt reflection device, even if the wavelength and spot size of the incident laser change, the same transverse phase structure can be obtained, the operation is simple, and a wide range of wavelength adjustment in the X-ray band can be achieved; the converged shaped laser can interact with a high-energy electron beam in a radiator, thereby generating short-wavelength and high-power coherent vortex light.

[0011] On the other hand, the present invention provides a vortex light generating device, including an injector, a first radiator, a second radiator and the laser transverse phase shaping system as described above, wherein the injector, the first radiator, the laser transverse phase shaping system and the second radiator are arranged in sequence, the injector is used to generate a high-energy electron beam, the first radiator is used to generate an incident laser, the laser transverse phase shaping system is used to perform phase shaping on the incident laser to obtain a converged shaped laser, and transmit the converged shaped laser to the second radiator, and the second radiator is used to allow the high-energy electron beam and the converged shaped laser to interact therein and generate short-wavelength and high-power coherent vortex light.

[0012] Furthermore, the first radiator is a self-amplified spontaneous radiator.

[0013] Furthermore, the second radiator includes an undulator, which is used to provide a transverse magnetic field and a periodic staggered magnetic field, so that the high-energy electron beam radiates to obtain short-wavelength and high-power coherent vortex light.

[0014] Furthermore, a crank structure is provided between the first radiator and the second radiator, and the crank structure is used to separate the high-energy electron beam emitted from the first radiator from the incident laser, and to recombine the high-energy electron beam with the converged shaped laser and inject them into the second radiator together.

[0015] Furthermore, the crank structure includes a first magnetic element, a second magnetic element, a third magnetic element and a fourth magnetic element arranged in sequence along the transmission direction of the electron beam, and the first magnetic element, the second magnetic element, the third magnetic element and the fourth magnetic element are all used to deflect the transmission direction of the high-energy electron beam.

[0016] Furthermore, the laser transverse phase shaping system is located between the first magnetic element and the fourth magnetic element, and a second concave reflector is provided between the first magnetic element and the wavefront tilt reflection device, and the second concave reflector is used to converge the incident laser and make the converged incident laser irradiate the wavefront tilt reflection device.

[0017] The vortex light generating device of the present invention utilizes a converged shaped laser to modulate a high-energy electron beam so that the high-energy electron beam generates high-energy vortex light in the short-wavelength band of X-rays in a second radiator. Since the wavelengths of the incident laser and the converged shaped laser can be adjusted, the vortex radiation generated by the second radiator is also tunable within the short-wavelength range and has high power. The converged shaped laser acts as a seed laser to act on the high-energy electron beam, thereby ensuring the coherence of the vortex radiation. Since the electron beam after acting on the converged shaped laser has a specific lateral structure, the electron beam can generate super-strong initial vortex radiation and can be rapidly amplified within a very short distance. Therefore, the present invention has a bright application prospect. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 is a side view of a laser transverse phase shaping system according to an embodiment of the present invention; Figure 2 is a stereoscopic diagram of a wavefront tilt reflection device of a laser transverse phase shaping system according to an embodiment of the present invention; Figure 3 is a schematic structural diagram of a vortex light generating device according to an embodiment of the present invention; Figure 4 Schematic diagram of a crank structure of a vortex light generating device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0019] The preferred embodiments of the present invention are given below in conjunction with the accompanying drawings and described in detail.

[0020] like Figure 1As shown, an embodiment of the present invention provides a laser transverse phase shaping system 100, which includes a wavefront tilt reflection device 110 and a first concave reflection mirror 120. The wavefront tilt reflection device 110 and the first concave reflection mirror 120 are arranged in sequence along the laser transmission direction and are located in the same vertical plane. The wavefront tilt reflection device 110 is used to shape the transverse phase of the incident laser 310 to obtain a shaped laser 130, and transmit the shaped laser 110 to the first concave reflection mirror 120. The first concave reflection mirror 120 is used to converge the shaped laser 130 to obtain a converged shaped laser 140, and transmit it in a preset direction.

[0021] like Figure 2 As shown, in some embodiments, the wavefront tilt reflection device 110 includes a first reflection plate 111, a second reflection plate 112 and a rotation axis 113. The first reflection plate 111 and the second reflection plate 112 are connected to the rotation axis 113 and can rotate around the rotation axis 113 independently. The incident laser 310 can be incident on the first reflection plate 111 and the second reflection plate 112. The rotation of the first reflection plate 111 and the second reflection plate 112 can change the incident angle of the incident laser 310 on the first reflection plate 111 and the second reflection plate 112, so as to change the phase of the incident laser 310 at the same lateral position. After reflection, the lateral phase difference value of the incident laser 310 It can be expressed as: , in, is the spot size of the incident laser 310, is the angle between the first reflector 111 and the second reflector 112, is the wavelength of the incident laser 310. The general value is , so that the first reflector 111 and the second reflector 112 are superimposed to obtain The phase shaping of the incident laser 310 is to shape the phase of one wavelength. When the wavelength and spot size of the incident laser 310 change, the angle between the two can be changed by rotating the first reflector 111 and / or the second reflector 112, so as to stabilize the amplitude of the lateral phase shaping, thereby realizing a wide range of wavelength adjustment in the X-ray band. For example, when hour, Micrometer, Micro-arc, nanometer.

[0022] The surfaces of the first reflector 111 and the second reflector 112 are both provided with a reflective coating for reflecting laser light. The surface of the first concave reflector 120 is also provided with a reflective coating for converging the laser light so that its optical path remains on the same axis.

[0023] The first reflector 111 and the second reflector 112 have different tilt angles, so that the incident laser 310 is divided into two shaped lasers 130 with different optical paths after being reflected by the first reflector 111 and the second reflector 112. The first concave reflector 120 can converge the shaped lasers 130 with different optical paths, so that they converge again to obtain the converged shaped lasers 140, and the converged shaped lasers 140 are transmitted along a preset direction. The converged shaped lasers 140 can interact with the high-energy electron beam in the radiator, so that the high-energy electron beam generates coherent vortex light with a short wavelength of X-rays that meets the requirements.

[0024] The laser transverse phase shaping system of the embodiment of the present invention can adjust the transverse phase structure of the incident laser 310 through the wavefront tilt reflection device 110 to obtain the shaped laser 130, and the first concave reflection mirror 120 converges the shaped laser 130 and changes its propagation direction, thereby generating a high-power transverse phase shaped laser with a controllable transverse phase structure; by changing the inclination angle of the first reflection plate 111 and the second reflection plate 112 of the wavefront tilt reflection device 110, even if the wavelength and spot size of the incident laser 310 change, the same transverse phase structure can be obtained, the operation is simple, and a wide range of wavelength adjustment in the X-ray band can be achieved; the converged shaped laser 140 can interact with the high-energy electron beam in the radiator, thereby generating short-wavelength and high-power coherent vortex light.

[0025] like Figure 3 As shown, an embodiment of the present invention further provides a vortex light generating device, including an injector 200, a first radiator 300, a second radiator 400 and the laser transverse phase shaping system 100 of the above embodiment, wherein the injector 200, the first radiator 300, the laser transverse phase shaping system 100 and the second radiator 400 are located on the same axis, the injector 200 is used to generate a high-energy electron beam, whose speed is close to the light beam and has a high energy density (on the order of 10GeV), the first radiator 300 is used to generate a short-wavelength and high-power incident laser 310, the laser transverse phase shaping system 100 is used to perform phase shaping on the incident laser 310 to obtain a converged shaped laser 140, and transmit the converged shaped laser 140 to the second radiator 400, and the second radiator 400 is used to make the high-energy electron beam and the converged shaped laser 140 interact therein and generate short-wavelength and high-power coherent vortex light.

[0026] In some embodiments, the first radiator 300 is a self-amplified spontaneous radiator. In the first radiator 300, the high-energy electron beam can spontaneously radiate to generate radiation light, and continuously couple with the spontaneous radiation light to cause the electron beam to produce micro-bunching, which in turn enhances the spontaneous radiation, thereby generating high-power incident laser.

[0027] like Figure 4 As shown, in some embodiments, a crank structure 500 may be further provided between the first radiator 300 and the second radiator 400. The crank structure 500 is used to change the transmission direction of the high-energy electron beam, so that the high-energy electron beam emitted from the first radiator 300 is separated from the incident laser 310, and the high-energy electron beam is recombined with the converged shaped laser 140 and incident on the second radiator 400 together. Specifically, the crank structure 500 can make the high-energy electron beam be transmitted along the first path, and the incident laser 310 be transmitted along the second path. The incident laser 310 is transmitted along the second path to the laser transverse phase shaping system 100, which shapes the incident laser 310 to obtain the converged shaped laser 140. The first path and the second path converge before the second radiator 400, so that the converged shaped laser 140 and the high-energy electron beam are combined before the second radiator 400 and incident on the second radiator 400 together.

[0028] The crank structure 500 may include a first magnetic element 510, a second magnetic element 520, a third magnetic element 530, and a fourth magnetic element 540 arranged in sequence along the first path, and each magnetic element is used to change the transmission direction of the high-energy electron beam. Specifically, after the high-energy electron beam passes through the first magnetic element 510, it will be deflected and deflected to the second magnetic element 520, and then deflected by the second magnetic element 520 to the third magnetic element 530, and then deflected by the third magnetic element 530 to the fourth magnetic element 540, and then deflected by the fourth magnetic element 540 to the second radiator 400, thereby causing the high-energy electron beam to be transmitted along the first path.

[0029] The first magnetic element 510 , the second magnetic element 520 , the third magnetic element 530 and the fourth magnetic element 540 may be, for example, a dipole iron or a quadrupole iron.

[0030] In some embodiments, the laser transverse phase shaping system 100 may be located between the first magnetic element 510 and the fourth magnetic element 540, and a second concave reflector 600 is provided between the wavefront tilt reflection device 110 and the first magnetic element 510. When the incident laser 310 passes through the first magnetic element 510, the first magnetic element 510 will not affect its transmission path, so it will be transmitted along the original path to the second concave reflector 600. The second concave reflector 600 is used to converge the incident laser 310 and transmit the converged incident laser 310 to the wavefront tilt reflection device 110, thereby improving the convergence degree of the incident laser 310 and making the vortex light generation effect better.

[0031] After the converged shaped laser 140 and the high-energy electron beam enter the second radiator 400, they will interact with each other, causing the high-energy electron beam to also have the transverse phase distribution of the laser 140. At this time, the laser generated by the micro-beam composed of the two in the second radiator 400 will have a laser with a continuously changing transverse phase, which is the required vortex light.

[0032] In some embodiments, the second radiator 400 may include an undulator for providing a transverse magnetic field with a periodic staggered magnetic field, so that a high-energy electron beam with a specific transverse phase structure is radiated to obtain short-wavelength and high-power coherent vortex light.

[0033] The vortex light generating device of the embodiment of the present invention utilizes the converged shaped laser 140 to modulate the high-energy electron beam so that the high-energy electron beam generates high-energy vortex light in the short-wavelength band of X-rays in the second radiator 400. Since the wavelengths of the incident laser 310 and the converged shaped laser 140 can be adjusted, the vortex radiation generated by the second radiator 400 is also tunable within the short wavelength range and has high power. The converged shaped laser 140 acts as a seed laser to interact with the high-energy electron beam to ensure the coherence of the vortex radiation. Since the electron beam after interacting with the converged shaped laser 140 has a specific lateral structure, the electron beam can generate super-strong initial vortex radiation and can be rapidly amplified within a very short distance. Therefore, the present invention has a bright application prospect.

[0034] The above is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention. The above embodiment of the present invention can also be modified in various ways. That is, all simple, equivalent changes and modifications made according to the claims and the description of the present invention fall within the scope of protection of the claims of the present invention. The contents not described in detail in the present invention are all conventional technical contents.

Claims

1. A laser transverse phase shaping system, characterized in that: It includes a wavefront tilted reflection device and a first concave reflection mirror, which are arranged in sequence along the laser transmission direction and are located in the same vertical plane. The wavefront tilted reflection device is used to shape the transverse phase of the incident laser to obtain a shaped laser, and transmit the shaped laser to the first concave reflection mirror; the first concave reflection mirror is used to converge the shaped laser to obtain the converged shaped laser.

2. The laser transverse phase shaping system according to claim 1, characterized in that: The wavefront tilt reflection device includes a first reflection plate, a second reflection plate and a rotation axis, wherein the first reflection plate and the second reflection plate are connected to the rotation axis and can rotate around the rotation axis independently; the incident laser is incident on the first reflection plate and the second reflection plate.

3. The laser transverse phase shaping system according to claim 2, characterized in that: The first reflecting plate and the second reflecting plate are configured to change the incident angle of the incident laser on the first reflecting plate and the second reflecting plate by rotating around the rotation axis, so as to change the phase of the incident laser at the same lateral position.

4. The laser transverse phase shaping system according to claim 2, characterized in that: The first reflector, the second reflector and the first concave reflector are all provided with a reflective coating layer.

5. A vortex light generating device, characterized in that: The invention comprises an injector, a first radiator, a second radiator and a laser transverse phase shaping system as described in any one of claims 1 to 4, wherein the injector, the first radiator, the laser transverse phase shaping system and the second radiator are arranged in sequence, the injector is used to generate a high-energy electron beam, the first radiator is used to generate an incident laser, the laser transverse phase shaping system is used to perform phase shaping on the incident laser to obtain a converged shaped laser, and transmit the converged shaped laser to the second radiator, and the second radiator is used to allow the high-energy electron beam and the converged shaped laser to interact therein and generate short-wavelength and high-power coherent vortex light.

6. The vortex light generating device according to claim 5, characterized in that: The first radiator is a self-amplified spontaneous radiator.

7. The vortex light generating device according to claim 5, characterized in that: The second radiator includes an undulator, which is used to provide a transverse magnetic field and a periodically staggered magnetic field so that the high-energy electron beam radiates to obtain short-wavelength and high-power coherent vortex light.

8. The vortex light generating device according to claim 5, characterized in that: A crank structure is also provided between the first radiator and the second radiator, and the crank structure is used to separate the high-energy electron beam emitted from the first radiator from the incident laser, and to recombine the high-energy electron beam with the converged shaped laser and inject them into the second radiator together.

9. The vortex light generating device according to claim 8, characterized in that: The crank structure includes a first magnetic element, a second magnetic element, a third magnetic element and a fourth magnetic element arranged in sequence along the transmission direction of the electron beam. The first magnetic element, the second magnetic element, the third magnetic element and the fourth magnetic element are all used to deflect the transmission direction of the high-energy electron beam.

10. The vortex light generating device according to claim 9, characterized in that: The laser transverse phase shaping system is located between the first magnetic element and the fourth magnetic element. A second concave reflector is provided between the first magnetic element and the wavefront tilt reflector. The second concave reflector is used to converge the incident laser and make the converged incident laser irradiate the wavefront tilt reflector.

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