Ultra-intense vortex laser phase measurement method

Abstract

A super-intense vortex laser phase measurement method includes: an incident Gaussian laser pulse is divided into two paths, one Gaussian laser pulse is used as a reference light, and the other Gaussian laser pulse is passed through an off-axis phase plate to generate a super-intense vortex laser as an object light; the Gaussian laser pulse and the super-intense vortex laser are then split into four beams to obtain a Gaussian laser pulse. E r 、 E r(1) 、 E r(2) 、 E r(3) and ultra-intense vortex laser E o 、 E o(1) 、 E o(2) 、 E o(3) ; Ultra-strong vortex laser E o(1) With Gaussian laser pulses E r(1) Synthetic interference laser E i ; Ultra-strong vortex laser E o(2) After introducing the phase of #imgabs0# and Gaussian laser pulse E r(2) Synthetic interference laser E i,π / 2 ;Detection laser E i,π / 2 、 E r 、 E o 、 E i The depth information of the surface plasmon holographic grating formed on the surface of the plasma target is obtained, thereby realizing the precise measurement of the phase distribution of the ultra-strong vortex laser.

Description

Technical Field

[0001] The invention belongs to the technical field of laser and plasma, and in particular to a method for measuring the phase of an ultra-strong vortex laser. Background Art

[0002] Plasmon holographic gratings, as an advanced plasma optical device, have been applied in various fields, especially in generating vortex lasers of relativistic intensity.

[0003] Relativistic vortex laser-plasma interactions have attracted extensive attention over the past few decades. With their helical electromagnetic fields and unique orbital angular momentum (OAM), vortex lasers have become a unique tool for accelerating and manipulating relativistic charged particles, and have enabled in-depth studies of angular momentum (AM) transfer between charged particles and fields under strong field conditions. However, these exciting theoretical and numerical studies rely heavily on the relativistic intensity and high-quality vortex phase of vortex lasers.

[0004] To advance experimental studies of relativistic vortex laser-plasma interactions, various theoretical and numerical schemes for generating relativistic intensity vortex lasers have been proposed. For theoretical or simulation-based studies, the precise three-dimensional structure of the desired plasma target in these schemes requires high laser temporal contrast, making them unsuitable for high-repetition-rate laser systems.

[0005] In addition, vortex lasers rely on the energy transfer between particles, electrostatic waves, and electromagnetic waves through Raman amplification or Brillouin scattering amplification, which limits their ability to further increase the intensity of vortex lasers. In the experiment, the maximum intensity of vortex lasers generated using a reflective phase plate or an off-axis spiral phase mirror remained at 10 20 W / cm 2 To further increase the output intensity, the diameter of the optical element must be continuously increased.

[0006] In addition, it has become a consensus among researchers in this field that the measurement of the vortex phase of relativistic intensity vortex laser is of great significance in experiments, but there is currently no effective measurement method. Summary of the Invention

[0007] In view of the problems existing in the prior art, the present invention proposes a super-intense vortex laser phase measurement method.

[0008] In order to achieve the above technical objectives, the technical solution adopted by the present invention is:

[0009] In one aspect, the present invention provides a method for measuring the phase of an ultra-intense vortex laser, comprising:

[0010] The incident Gaussian laser pulse is split into two beams. One of the split Gaussian laser pulses is used as the reference light, and the other Gaussian laser pulse is generated as the object light after passing through the off-axis phase plate.

[0011] The Gaussian laser pulse as the reference light is split into four beams, namely Gaussian laser pulse E r 、 E r(1) 、 E r(2) 、 E r(3) ;

[0012] The ultra-intense vortex laser beam as the object beam is split into four beams, namely ultra-intense vortex laser E o 、 E o(1) 、 E o(2) 、 E o(3) ;

[0013] A beam of ultra-intense vortex laser E o(1) With a Gaussian laser pulse E r(1) Synthetic interference laser E i ;

[0014] A beam of ultra-intense vortex laser E o(2) In the introduction After the phase of another Gaussian laser pulse E r(2) Synthetic interference laser E i,π / 2 ;

[0015] Detection laser E i,π / 2 、 E r 、 E o 、 E i The phase distribution of the ultra-intense vortex laser is measured using the depth information of the surface plasmon holographic grating formed on the surface of the plasma target.

[0016] Furthermore, the phase distribution of the ultra-intense vortex laser Expressed as:

[0017] ;

[0018] in Indicated by interferometric laserE i,π / 2 The surface plasmon holographic grating formed in Depth in coordinates, Indicated by laser E o The surface plasmon holographic grating formed in Depth in coordinates, Indicated by laser E r The surface plasmon holographic grating formed in Depth in coordinates, Interference laser E i The surface plasmon holographic grating formed in Depth in coordinates.

[0019] Preferably, the Gaussian laser pulse of the present invention E r(3) , ultra-strong vortex laser E o(3) Output directly to free space.

[0020] On the other hand, in order to realize the above-mentioned ultra-intense vortex laser phase measurement method, the present invention also proposes an ultra-intense vortex laser phase measurement device, comprising a plurality of beam splitters, a plurality of reflectors, a plurality of beam combiners, a plurality of off-axis parabolic mirrors, a plasma target and a detection unit, wherein each beam splitter is used to split the light beam incident on the beam splitter into two paths and then output them;

[0021] The incident Gaussian laser pulse is incident on the first beam splitter and is split into two paths by the first beam splitter. One Gaussian laser pulse is used as the reference light, and the other Gaussian laser pulse obtained by the beam splitting passes through the off-axis phase plate and is converted into an ultra-strong vortex laser by the off-axis phase plate as the object light.

[0022] The ultra-strong vortex laser output by the off-axis phase plate is reflected to the fifth beam splitter, and the laser reflected by the fifth beam splitter is incident on the sixth beam splitter. The laser transmitted by the sixth beam splitter is reflected and output by the fourth reflector; the laser output transmitted by the fifth beam splitter is incident on the seventh beam splitter, and the ultra-strong vortex laser is reflected by the seventh beam splitter. E o ;

[0023] The pulsed laser reflected by the first beam splitter is incident on the second beam splitter, the laser reflected by the second beam splitter is incident on the fourth beam splitter, the laser transmitted by the fourth beam splitter is incident on the third reflector, reflected and output by the third reflector, the laser reflected by the fourth beam splitter is incident on the second reflector, reflected by the second reflector to the first beam combiner, and the laser reflected by the sixth beam splitter is also incident on the first beam combiner. The first beam combiner combines the beams and outputs an interference laser with a phase difference of 0E i ;

[0024] The laser transmitted through the second beam splitter is incident on the third beam splitter, and the laser transmitted through the third beam splitter is incident on the first reflector, and the first reflector reflects the Gaussian laser pulse. E r ;

[0025] The laser transmitted through the seventh beam splitter is incident on the fifth reflector, reflected by the fifth reflector to the sixth reflector, and reflected by the sixth reflector to the second beam combiner. The laser reflected by the third beam splitter is also incident on the second beam combiner. By adjusting the positions of the fifth and sixth reflectors in the optical path, the laser reflected by the fifth and sixth reflectors to the second beam combiner has the same wavelength as the laser reflected by the third beam splitter. Phase difference, the second combiner output has Phase-difference interferometric laser E i,π / 2 ;

[0026] laser E i,π / 2 ,laser E r ,laser E o ,laser E i The laser beam is incident on different positions of the plasma target surface through the first off-axis parabolic mirror, the second off-axis parabolic mirror, the third off-axis parabolic mirror and the fourth off-axis parabolic mirror respectively. The detection unit detects the laser beam. E i,π / 2 ,laser E r ,laser E o ,laser E i The depth information of the surface plasmon holographic grating formed by irradiating the plasma target surface is based on the laser E i,π / 2 ,laser E r ,laser E o ,laser E i The depth information of the surface plasmon holographic grating formed by irradiating the plasma target surface can be used to measure the phase distribution of the ultra-intense vortex laser.

[0027] Furthermore, the intensity of the ultra-intense vortex laser 10 16 W / cm 2 .

[0028] Furthermore, the detection unit is a plasma density distribution detection unit, which uses visible light, near infrared light or X-ray detection laser E i,π / 2 ,laser E r ,laser E o ,laser E i The plasma density distribution of the surface plasmon holographic grating formed on the surface of the plasma target is irradiated, and the depth information is obtained.

[0029] The present invention provides a method for measuring the phase distribution of ultra-intense vortex laser, and provides an effective method for measuring and recording the vortex phase of relativistic object light. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying any creative work.

[0031] Figure 1 Schematic diagram of the structure of a depth information measurement device of a surface plasmon holographic grating in one embodiment;

[0032] Figure 2 The schematic diagrams of the surface plasmon holographic grating (SPH) and the generation of ultra-intense vortex lasers are shown, where (a) shows a schematic diagram of the object light and reference light synchronously irradiating the surface of the plasma target and interfering with each other, and (b) shows a schematic diagram of the surface plasmon holographic grating formed when the object light and reference light are synchronously irradiated on the surface of the plasma target at 0 ps, ​​0.5 ps, and 1 ps, where ps represents picoseconds;

[0033] Figure 3 The depth distribution diagram of the surface plasmon holographic grating (SPH) under different conditions in one embodiment, where (a) shows the interference laser with a phase difference of 0 E i The depth distribution of the surface plasmon holographic grating formed by irradiating the plasma target surface, (b) shows the Phase-difference interferometric laser E i,π / 2 The depth distribution of the surface plasmon holographic grating formed by irradiating the plasma target surface, (c) shows the laser E oThe depth distribution of the surface plasmon holographic grating formed by irradiating the plasma target surface, (d) shows the laser E i Depth distribution of the surface plasmon holographic grating formed by irradiating the plasma target surface.

[0034] Figure 4 Theoretical and simulated phase distributions of the reconstructed object light and the phase-derived laser electric field diagrams, where (a) shows the phase distribution of the reconstructed object light obtained by theoretical calculation, (b) shows the phase distribution of the reconstructed object light obtained by simulation, (c) shows the electric field distribution of the reconstructed object light obtained by theoretical calculation, and (d) shows the electric field distribution of the reconstructed object light obtained by simulation.

[0035] Figure 5 Depth distribution of surface plasmon holographic grating (SPH) under different conditions, where (a) shows the interference laser E i The density distribution of the formed surface plasmon holographic grating (SPH), (b) shows the interference laser E i,π / 2 The density distribution of the surface plasmon holographic grating (SPH) formed by the laser is shown in (c). E o (i.e., only with object light) the surface plasmon holographic grating (SPH) density distribution diagram, (d) shows the laser E r (i.e., with only reference light) forming a plasma holographic grating (SPH) density distribution map;

[0036] Figure 6 The phase distribution of the object light and the distribution of the laser electric field under high-order modes and oblique incidence obtained by theoretical calculation are shown, where (a) shows (a) shows the phase distribution of the object light in the high-order mode under the condition of (b), (c) shows the laser electric field distribution of the object light in the high-order mode under the condition of oblique incidence, and (d) shows the laser electric field distribution of the object light in the case of oblique incidence.

[0037] Numbers in the figure:

[0038] 1. First beam splitter; 2. Second beam splitter; 3. Third beam splitter; 4. First reflector; 5. Fourth beam splitter; 6. Second reflector; 7. Third reflector; 8. Off-axis phase plate; 9. Fifth beam splitter; 10. Sixth beam splitter; 11. Fourth reflector; 12. Seventh beam splitter; 13. First beam combiner; 14. Second beam combiner; 15. Fifth reflector; 16. Sixth reflector; 17. First off-axis parabolic mirror; 18. Second off-axis parabolic mirror; 19. Third off-axis parabolic mirror; 20. Fourth off-axis parabolic mirror; 21. Plasma target; 22. Detection unit.

[0039] The purpose, features and advantages of the present invention will be further described with reference to the accompanying drawings and in conjunction with the embodiments. DETAILED DESCRIPTION

[0040] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clearly understood, the following drawings and detailed descriptions clearly illustrate the spirit of the present invention. After understanding the embodiments of the present invention, any person skilled in the art will be able to make changes and modifications based on the techniques taught by the present invention without departing from the spirit and scope of the present invention. The exemplary embodiments of the present invention and their descriptions are intended to illustrate the present invention and are not intended to limit the present invention.

[0041] In one embodiment, a method for measuring the phase of an ultra-intense vortex laser is provided, comprising:

[0042] The incident Gaussian laser pulse is split into two beams. One of the split Gaussian laser pulses is used as the reference light, and the other Gaussian laser pulse is generated as the object light after passing through the off-axis phase plate.

[0043] The Gaussian laser pulse as the reference light is split into four beams, namely Gaussian laser pulse E r 、 E r(1) 、 E r(2) 、 E r(3) ;

[0044] The ultra-intense vortex laser beam as the object beam is split into four beams, namely ultra-intense vortex laser E o 、 E o(1) 、 E o(2) 、 E o(3) ;

[0045] A beam of ultra-intense vortex laser E o(1) With a Gaussian laser pulseE r(1) Synthetic interference laser E i ;

[0046] A beam of ultra-intense vortex laser E o(2) In the introduction After the phase of another Gaussian laser pulse E r(2) Synthetic interference laser E i,π / 2 ;

[0047] Detection laser E i,π / 2 、 E r 、 E o 、 E i The phase distribution of the ultra-intense vortex laser is measured using the depth information of the surface plasmon holographic grating formed on the surface of the plasma target.

[0048] Phase distribution of ultra-intense vortex laser Expressed as:

[0049] ;

[0050] in Indicated by interferometric laser E i,π / 2 The surface plasmon holographic grating formed in Depth in coordinates, Indicated by laser E o The surface plasmon holographic grating formed in Depth in coordinates, Indicated by laser E r The surface plasmon holographic grating formed in Depth in coordinates, Interference laser E i The surface plasmon holographic grating formed in Depth in coordinates.

[0051] The depth information of the surface plasmon holographic grating can be characterized by the plasma density on the plasma target surface. The plasma density on the plasma target surface is the change in the distance on the x-axis, i.e., the normal direction perpendicular to the plasma target surface, corresponding to a certain value and before the interaction with the laser, which is also the depth of the plasma holographic grating.

[0052] Reference Figure 1One embodiment provides an ultra-strong vortex laser phase measurement device, including multiple beam splitters, multiple reflectors, multiple beam combiners, multiple off-axis parabolic mirrors, a plasma target and a detection unit, wherein each beam splitter is used to split the light beam incident on the beam splitter into two paths and then output them.

[0053] The incident Gaussian laser pulse is incident on the first spectrometer 1 and is split into two paths by the first spectrometer 1. One Gaussian laser pulse is used as the reference light, and the other Gaussian laser pulse obtained by the splitting passes through the off-axis phase plate 8 and is converted into an ultra-strong vortex laser by the off-axis phase plate 8 as the object light.

[0054] The ultra-strong vortex laser output by the off-axis phase plate 8 is reflected to the fifth beam splitter 9, and the laser beam reflected by the fifth beam splitter 9 is incident on the sixth beam splitter 10. The laser beam transmitted by the sixth beam splitter 10 is reflected and output by the fourth reflector 11; the laser beam transmitted by the fifth beam splitter 9 is incident on the seventh beam splitter 12, and the ultra-strong vortex laser beam is reflected by the seventh beam splitter 12. E o ; wherein the intensity of the ultra-strong vortex laser 10 16 W / cm 2 .

[0055] The pulsed laser reflected by the first beam splitter 1 is incident on the second beam splitter 2, the laser reflected by the second beam splitter 2 is incident on the fourth beam splitter 5, the laser transmitted by the fourth beam splitter 5 is incident on the third reflector 7, reflected and output by the third reflector 7, the laser reflected by the fourth beam splitter 5 is incident on the second reflector 6, reflected by the second reflector 6 to the first beam combiner 13, and at the same time, the laser reflected by the sixth beam splitter 10 is also incident on the first beam combiner 13, and the first beam combiner 13 combines the beams and outputs an interference laser with a phase difference of 0 E i ;

[0056] The laser beam transmitted through the second beam splitter 2 is incident on the third beam splitter 3, and the laser beam transmitted through the third beam splitter 3 is incident on the first reflector 4, and the Gaussian laser pulse is reflected by the first reflector 4. E r ;

[0057] The laser light transmitted through the seventh beam splitter 12 is incident on the fifth reflector 15, reflected by the fifth reflector 15 to the sixth reflector 16, and reflected by the sixth reflector to the second beam combiner 14. The laser light reflected by the third beam splitter 3 is also incident on the second beam combiner 14. By adjusting the positions of the fifth reflector 15 and the sixth reflector 16 in the optical path, the laser light reflected by the fifth reflector 15 and the sixth reflector 16 to the second beam combiner 14 has the same wavelength as the laser light reflected by the third beam splitter 3. Phase difference, the combined output of the second combiner 14 has Phase-difference interferometric laser E i,π / 2 ;

[0058] laser E i,π / 2 ,laser E r ,laser E o ,laser E i The laser beam is incident on different positions of the surface of the plasma target 21 through the first off-axis parabolic mirror 17, the second off-axis parabolic mirror 18, the third off-axis parabolic mirror 19 and the fourth off-axis parabolic mirror 20 respectively. The detection unit 22 detects the laser beam. E i,π / 2 ,laser E r ,laser E o ,laser E i The depth information of the surface plasmon holographic grating formed by irradiating the plasma target surface is based on the laser E i,π / 2 ,laser E r ,laser E o ,laser E i The depth information of the surface plasmon holographic grating formed by irradiating the plasma target surface can be used to measure the phase distribution of the ultra-intense vortex laser.

[0059] The detection unit is a plasma density distribution detection unit, which can use visible light, near infrared light or X-ray detection laser. E i,π / 2 ,laser E r ,laser E o ,laser E i The plasma density distribution of the surface plasmon holographic grating formed on the surface of the plasma target is irradiated, and the depth information is obtained.

[0060] In the above embodiment, the laser E o As an object light, laser E r As the reference light. The intensity of the object light 10 16 W / cm 2 , the intensity of the reference light 10 16 W / cm 2 Interferometric laserE i,π / 2 Equivalent to having Interference light between the object light and the reference light with phase difference. Interference laser E i It is equivalent to the interference light between the object light and the reference light with a phase difference of 0.

[0061] The position adjustment method of the fifth reflector and the sixth reflector is not limited. For example, the fifth reflector and the sixth reflector can be mounted on a displacement platform (electric displacement platform or manual displacement platform), and the position of the fifth reflector and the sixth reflector in the optical path can be adjusted by the displacement platform so that the laser reflected by the fifth reflector and the sixth reflector to the second beam combiner has a certain optical path. Phase difference. Regarding the design of the displacement platform, many optical path structures in this field include displacement adjustment structure / equipment design, and there are also many mature displacement platform designs in the mechanical field. They are generally composed of guide rails, drive sources, clamps, etc. The present invention does not impose specific restrictions on the displacement platform. Those skilled in the art can make reasonable choices in the existing technology based on their needs and application conditions.

[0062] Figure 2 The schematic diagrams of the surface plasmon holographic grating (SPH) and ultra-intense vortex laser generation are shown, where (a) shows a schematic diagram of the object light and the reference light synchronously irradiating the surface of the plasma target and interfering with each other, and (b) shows a schematic diagram of the surface plasmon holographic grating formed when the object light and the reference light are synchronously irradiated on the surface of the plasma target at 0ps, 0.5ps and 1ps, where ps represents picoseconds; a beam of object light 1 and a beam of reference light 2 are simultaneously irradiated on the surface of the plasma target and interfere with each other to form a surface plasmon holographic grating 3.

[0063] The basic characteristic of surface plasmon holographic grating (SPH) is that it can record, store and recover the phase of light beam.

[0064] Figure 3 The depth distribution diagram of the surface plasmon holographic grating (SPH) under different conditions in one embodiment, where (a) shows the interference laser with a phase difference of 0 E i The depth distribution of the surface plasmon holographic grating formed by irradiating the plasma target surface, (b) shows the Phase-difference interferometric laser E i,π / 2 The depth distribution of the surface plasmon holographic grating formed by irradiating the plasma target surface, (c) shows the laser E o The depth distribution of the surface plasmon holographic grating formed by irradiating the plasma target surface, (d) shows the laser Ei Depth distribution of the surface plasmon holographic grating formed by irradiating the plasma target surface.

[0065] Figure 4 Theoretical and simulated phase distributions of the reconstructed object light and the phase-derived laser electric field diagrams are shown, where (a) shows the phase distribution of the reconstructed object light obtained by theoretical calculation, (b) shows the phase distribution of the reconstructed object light obtained by simulation, (c) shows the electric field distribution of the reconstructed object light obtained by theoretical calculation, and (d) shows the electric field distribution of the reconstructed object light obtained by simulation. Since the surface plasmon holographic grating (SPH) is formed under laser irradiation, it is assumed that the depth of the surface plasmon holographic grating (SPH) is positively correlated with the energy of laser deposition. The relationship between the depth of the surface plasmon holographic grating (SPH) and the laser energy can be expressed as: ,in is the reference light intensity at the plasma target surface, the pulse duration of the object light and the pulse duration of the reference light Both In order to reconstruct the phase profile of the object light, the laser E i,π / 2 ,laser E r ,laser E o ,laser E i Four cases of surface plasmon holographic gratings formed by irradiating the plasma target surface. Since the same laser duration is used, the The phase of the object light can be expressed as:

[0066] ;

[0067] in Indicated by interferometric laser E i,π / 2 The surface plasmon holographic grating formed in Depth in coordinates, Indicated by laser E o The surface plasmon holographic grating formed in Depth in coordinates, Indicated by laser E r The surface plasmon holographic grating formed in Depth in coordinates, Interference laser E i The surface plasmon holographic grating formed in Depth in coordinates.

[0068] It can be seen from the formula that in the simulation process, only the laser E i,π / 2 ,laser E r ,laser E o ,laser E i The depth information of the surface plasmon holographic grating formed on the plasma target surface can be used to measure the phase distribution of the object light. The spiral phase distribution of the object light and the corresponding electric field pattern are obtained from Figure 4 As can be clearly seen in the figure, a high degree of agreement is demonstrated between the theoretical measurements and the simulation results. In addition, the use of data processing algorithms may further improve the precision and accuracy of phase reconstruction.

[0069] Figure 5 Depth distribution of surface plasmon holographic grating (SPH) under different conditions, where (a) shows the interference laser E i The density distribution of the formed surface plasmon holographic grating (SPH), (b) shows the interference laser E i,π / 2 The density distribution of the surface plasmon holographic grating (SPH) formed by the laser is shown in (c). E o (i.e., only with object light) the surface plasmon holographic grating (SPH) density distribution diagram, (d) shows the laser E r (i.e., with only reference light) to form a plasma holographic grating (SPH) density distribution diagram; Figure 5 As shown in (a)-(b), when the initial phase of the object light is changed, the pattern of the surface plasmon holographic grating (SPH) remains unchanged but rotates.

[0070] Figure 6 The phase distribution of the object light and the distribution of the laser electric field under high-order modes and oblique incidence obtained by theoretical calculation are shown, where (a) shows (a) shows the phase distribution of the object light in the high-order mode, (b) shows the phase distribution of the object light in the case of oblique incidence, (c) shows the laser electric field distribution of the object light in the high-order mode, and (d) shows the laser electric field distribution of the object light in the case of oblique incidence. In order to verify the applicability of the phase measurement method in high-order modes and oblique incidence, the phase distribution and corresponding electric field distribution in these two cases were theoretically calculated. As shown in Figures (a)-(d), the theoretical results show that the object light The phase distribution and electric field distribution of the object beam under modal and oblique incidence demonstrate the robustness of the method.

[0071] Matters not covered by the present invention are known technologies.

[0072] The technical features of the above embodiments can be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0073] The above-described embodiments merely represent several implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention. It should be noted that a person of ordinary skill in the art may make various modifications and improvements without departing from the spirit of the present application, and such modifications and improvements are intended to fall within the scope of protection of the present application. Therefore, the scope of protection of the present application shall be determined by the appended claims.

Claims

1. Ultra-strong vortex laser phase measurement method, characterized in that: include: The incident Gaussian laser pulse is split into two beams. One of the split Gaussian laser pulses is used as the reference light, and the other Gaussian laser pulse is generated as the object light after passing through the off-axis phase plate. The Gaussian laser pulse as the reference light is split into four beams, namely Gaussian laser pulse E r 、 E r(1) 、 E r(2) 、 E r(3) ; The ultra-intense vortex laser beam as the object beam is split into four beams, namely ultra-intense vortex laser E o 、 E o(1) 、 E o(2) 、 E o(3) ; A beam of ultra-intense vortex laser E o(1) With a Gaussian laser pulse E r(1) Synthetic interference laser E i ; A beam of ultra-intense vortex laser E o(2) In the introduction After the phase of another Gaussian laser pulse E r(2) Synthetic interference laser E i,π / 2 ; Detection laser E i,π / 2 、 E r 、 E o 、 E i The phase distribution of the ultra-intense vortex laser is measured using the depth information of the surface plasmon holographic grating formed on the surface of the plasma target.

2. The ultra-strong vortex laser phase measurement method according to claim 1, characterized in that: Phase distribution of ultra-intense vortex laser Expressed as: in Indicated by interferometric laser E i,π / 2 The surface plasmon holographic grating formed in Depth in coordinates, Indicated by laser E o The surface plasmon holographic grating formed in Depth in coordinates, Indicated by laser E r The surface plasmon holographic grating formed in Depth in coordinates, Interference laser E i The surface plasmon holographic grating formed in Depth in coordinates.

3. The ultra-strong vortex laser phase measurement method according to claim 1, characterized in that: Gaussian laser pulses E r(3) , ultra-strong vortex laser E o(3) Output directly to free space.

4. An ultra-intense vortex laser phase measurement device for implementing the ultra-intense vortex laser phase measurement method according to claim 1, characterized in that: It includes multiple beam splitters, multiple reflectors, multiple beam combiners, multiple off-axis parabolic mirrors, a plasma target and a detection unit, wherein each beam splitter is used to split the light beam incident on the beam splitter into two paths and then output them; The incident Gaussian laser pulse is incident on the first beam splitter and is split into two paths by the first beam splitter. One Gaussian laser pulse is used as the reference light, and the other Gaussian laser pulse obtained by the beam splitting passes through the off-axis phase plate and is converted into an ultra-strong vortex laser by the off-axis phase plate as the object light. The ultra-strong vortex laser output by the off-axis phase plate is reflected to the fifth beam splitter, and the laser reflected by the fifth beam splitter is incident on the sixth beam splitter. The laser transmitted by the sixth beam splitter is reflected and output by the fourth reflector; the laser output transmitted by the fifth beam splitter is incident on the seventh beam splitter, and the ultra-strong vortex laser is reflected by the seventh beam splitter. E o ; The pulsed laser reflected by the first beam splitter is incident on the second beam splitter, the laser reflected by the second beam splitter is incident on the fourth beam splitter, the laser transmitted by the fourth beam splitter is incident on the third reflector, reflected and output by the third reflector, the laser reflected by the fourth beam splitter is incident on the second reflector, reflected by the second reflector to the first beam combiner, and the laser reflected by the sixth beam splitter is also incident on the first beam combiner. The first beam combiner combines the beams and outputs an interference laser with a phase difference of 0 E i ; The laser transmitted through the second beam splitter is incident on the third beam splitter, and the laser transmitted through the third beam splitter is incident on the first reflector, and the first reflector reflects the Gaussian laser pulse. E r ; The laser transmitted through the seventh beam splitter is incident on the fifth reflector, reflected by the fifth reflector to the sixth reflector, and reflected by the sixth reflector to the second beam combiner. The laser reflected by the third beam splitter is also incident on the second beam combiner. By adjusting the positions of the fifth and sixth reflectors in the optical path, the laser reflected by the fifth and sixth reflectors to the second beam combiner has the same wavelength as the laser reflected by the third beam splitter. Phase difference, the second combiner output has Phase-difference interferometric laser E i,π / 2 ; laser E i,π / 2 ,laser E r ,laser E o ,laser E i The laser beam is incident on different positions of the plasma target surface through the first off-axis parabolic mirror, the second off-axis parabolic mirror, the third off-axis parabolic mirror and the fourth off-axis parabolic mirror respectively. The detection unit detects the laser beam. E i,π / 2 ,laser E r ,laser E o ,laser E i The depth information of the surface plasmon holographic grating formed by irradiating the plasma target surface is based on the laser E i,π / 2 ,laser E r ,laser E o ,laser E i The depth information of the surface plasmon holographic grating formed by irradiating the plasma target surface can be used to measure the phase distribution of the ultra-intense vortex laser.

5. The ultra-strong vortex laser phase measurement device according to claim 4, characterized in that: Phase distribution of ultra-intense vortex laser Expressed as: in Indicated by interferometric laser E i,π / 2 The surface plasmon holographic grating formed in Depth in coordinates, Indicated by laser E o The surface plasmon holographic grating formed in Depth in coordinates, Indicated by laser E r The surface plasmon holographic grating formed in Depth in coordinates, Interference laser E i The surface plasmon holographic grating formed in Depth in coordinates.

6. The ultra-strong vortex laser phase measurement device according to claim 4, characterized in that: The intensity of the ultra-intense vortex laser 10 16 W / cm 2 .

7. The ultra-intense vortex laser phase measurement device according to claim 4, characterized in that: The detection unit is a plasma density distribution detection unit, which uses visible light, near infrared light or X-ray detection laser E i,π / 2 ,laser E r ,laser E o ,laser E i The plasma density distribution of the surface plasmon holographic grating formed on the surface of the plasma target is irradiated, and the depth information is obtained.

8. The ultra-intense vortex laser phase measurement device according to claim 4, characterized in that: The fifth and sixth reflectors are mounted on a displacement platform, and their positions in the optical path are adjusted by the displacement platform so that the laser light reflected by the fifth and sixth reflectors to the second beam combiner has a certain optical path. Phase difference.

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