Optical parameter laser amplifier preparation method and related device

Abstract

The invention discloses an optical parametric laser amplifier preparation method and a related device, and the method comprises the steps: calculating the refractive indexes of pump light, signal light and idler frequency light in a crystal according to a high-order approximate dispersion equation of a Sellmeier equation and nonlinear crystal parameters; according to the refractive index and a multi-wavelength dispersion correction non-collinear phase matching formula, obtaining a multi-wavelength dispersion correction non-collinear phase matching equation of the pump light, the signal light and the idler frequency light in the crystal; searching the multi-wavelength dispersion correction non-collinear phase matching equation through a particle swarm optimization algorithm to obtain an optimal non-collinear angle and crystal parameters; and preparing an optical parameter laser amplifier system according to the optimal non-collinear angle and the crystal parameters so as to realize an efficient optical parameter amplification effect under preset wavelength and angle conditions. According to the obtained optimal non-collinear angle and crystal parameters, phase mismatch and energy loss in the optical parameter amplification process are reduced, and the optical parameter amplification effect can be maximized.

Description

Technical Field

[0001] The present invention relates to the field of laser technology, and in particular to a method and device for preparing an optical parametric laser amplifier, and a computing device. Background Art

[0002] As a nonlinear optical device, optical parametric laser amplifiers are crucial in scientific research and industrial applications. They mainly amplify optical signals through the optical parametric process of nonlinear crystals and have broad application prospects in optical communications, laser processing, spectral analysis, and ultrafast optics.

[0003] Although the existing technology has made certain progress in the preparation of optical parametric laser amplifiers, the refractive index of nonlinear crystals changes with temperature, causing the phase matching conditions to shift, thus affecting the efficiency and stability of optical parametric amplification. For example, in the process of optical parametric amplification, nonlinear crystals absorb laser energy and produce thermal effects, which has become a core factor restricting its development. The thermal effect will cause the temperature of the nonlinear crystal to change, causing it to deviate from the originally set phase matching temperature, thereby destroying the phase matching of the optical parametric laser amplifier, thereby reducing the energy conversion efficiency of pump light to signal light, and limiting the performance of the optical parametric laser amplifier. In addition, the existing preparation methods are usually optimized for specific wavelengths and angles, and it is difficult to adapt to the diverse needs in different application scenarios. Summary of the invention

[0004] In view of the above problems, the present invention is proposed to provide a method and apparatus for preparing an optical parametric laser amplifier and a computing device that overcome the above-mentioned phase mismatch and energy loss problems.

[0005] According to one aspect of the present invention, there is provided a method for preparing an optical parametric laser amplifier, comprising:

[0006] Calculating the refractive indexes of the pump light, the signal light and the idler light in the crystal according to the high-order approximate dispersion equation of the Sellmeier equation and the nonlinear crystal parameters; wherein the nonlinear crystal parameters at least include the Sellmeier coefficient, the crystal temperature and the wavelengths of the pump light, the signal light and the idler light;

[0007] According to the refractive index and the multi-wavelength dispersion correction non-collinear phase matching formula, a multi-wavelength dispersion correction non-collinear phase matching equation of the pump light, the signal light and the idler light in the crystal is obtained;

[0008] Searching the multi-wavelength dispersion correction non-collinear phase matching equation by a particle swarm optimization algorithm to obtain the optimal non-collinear angle and crystal parameters;

[0009] According to the optimal non-collinear angle and crystal parameters, an optical parametric laser amplifier system is prepared to achieve a highly efficient optical parametric amplification effect under preset wavelength and angle conditions.

[0010] In an optional manner, the calculation formula of the refractive index is:

[0011]

[0012] The calculation formula of the refractive index of the signal light in the crystal is:

[0013]

[0014] The calculation formula of the refractive index of the idler light in the crystal is:

[0015]

[0016] Among them, λ p ,λ s ,λ i are the wavelengths of pump light, signal light and idler light respectively; T is the temperature of the crystal; B i (T), C i (T) is the coefficient of the Sellmeier equation; m is the number of terms in the Sellmeier equation; n p , n s , n i are the refractive indices of pump light, signal light and idler light in the crystal respectively; α, β, γ are power term parameters; D j (T) is the higher-order dispersion coefficient; n is the number of higher-order terms.

[0017] In an optional manner, the multi-wavelength dispersion-corrected non-collinear phase matching equation is:

[0018]

[0019] Among them, n p (λ p ,T) is the pump light at wavelength λ p and the refractive index at temperature T; n s (λ s ,T) is the signal light at wavelength λ s and the refractive index at temperature T; n i (λ i ,T) is the idler light at wavelength λ i and the refractive index at temperature T; is the pump light wave vector The unit direction component of ; is the signal light wave vector The unit direction component of ; Idle frequency wave vector The unit direction component of G x , G y , G z is the crystal reciprocal lattice vector The amount.

[0020] In an optional manner, searching the multi-wavelength dispersion correction non-collinear phase matching equation by a particle swarm optimization algorithm to obtain the optimal non-collinear angle and crystal parameters further includes:

[0021] Determine optimization target variables, the target variables include non-collinear angles and crystal parameters; wherein the non-collinear angles include the angle between the signal light and the pump light and the angle between the idler light and the pump light, and the crystal parameters include temperature, crystal length, and cutting angle;

[0022] According to the objective function of the negative square value of the phase mismatch, the phase mismatch is minimized to achieve efficient nonlinear interaction; wherein the phase mismatch is obtained by subtracting the left side from the right side of the non-collinear phase matching equation;

[0023] A group of particles are randomly generated, and the squared negative value of the phase mismatch of each particle is evaluated; wherein each particle represents a set of non-collinear angles and crystal parameters;

[0024] For each particle, if the objective function value of the current position is better than the objective function value of its historical optimal position, its individual optimal solution is updated;

[0025] Among the individual optimal solutions of all particles, find the global optimal solution, that is, the particle with the largest objective function value;

[0026] Update the particle's speed and position based on the individual optimal solution, the global optimal solution, and the particle's current speed and position.

[0027] In an optional manner, the formula for updating the velocity and position of the particle is:

[0028] v id t+1=w·v id t+c1·r1·(p id -x id t)+c2·r2·(p g -x id t)

[0029]

[0030] Among them, v id t and x idt is the velocity and position of particle i in the dth dimension and the tth generation, w is the inertia weight, c1 and c2 are learning factors, r1 and r2 are random numbers, p id is the individual optimal solution of particle i, p g It is the global optimal solution.

[0031] In an optional manner, the preparing an optical parametric laser amplifier system according to the optimal non-collinear angle and crystal parameters further comprises:

[0032] Select nonlinear crystals based on the requirements of optical parametric amplification;

[0033] Process the crystal according to the cutting angle and length, and stabilize the crystal at the operating temperature to ensure that it meets the phase matching conditions;

[0034] The optical paths of the pump light and the signal light are adjusted so that they are incident on the nonlinear crystal at an optimal non-collinear angle.

[0035] In an optional manner, the method further includes:

[0036] The particle swarm optimization algorithm introduces a dynamic inertia weight. During the iteration process, the value of the inertia weight is dynamically adjusted so that it performs a global search with a larger value in the early stage of the search and gradually decreases in the later stage of the search to perform a local fine search, thereby balancing the global search ability and local convergence ability of the algorithm;

[0037] When a particle exceeds the preset search space boundary during the iteration process, it is pulled back into the search space by reflection or re-random generation to ensure the continuity of the search;

[0038] The maximum number of iterations and convergence conditions are set, and the iteration is stopped when any condition is met, and the optimal non-collinear angle and crystal parameters are output; wherein the convergence condition is that the change in the objective function value for consecutive preset generations is less than a preset threshold.

[0039] In an optional manner, the preparation of the optical parametric laser amplifier system further comprises:

[0040] According to the optimal non-collinear angle and crystal parameters, the pump light source, optical lens, reflector and filter are selected and assembled to form a stable optical path system;

[0041] Fix the nonlinear crystal in a temperature control device, and control the temperature of the crystal through the temperature control device to ensure that it maintains the optimal working temperature during the experiment;

[0042] After the optical path system is built, the optical paths of the pump light, signal light and idler light are adjusted, the non-collinear angle is optimized, and the position and temperature of the crystal are fine-tuned to achieve the best phase matching and optical parametric amplification effect.

[0043] According to another aspect of the present invention, there is provided a device for preparing an optical parametric laser amplifier, comprising:

[0044] A refractive index calculation module, used to calculate the refractive index of the pump light, the signal light and the idler light in the crystal according to the high-order approximate dispersion equation of the Sellmeier equation and the nonlinear crystal parameters; wherein the nonlinear crystal parameters at least include the Sellmeier coefficient, the crystal temperature and the wavelengths of the pump light, the signal light and the idler light;

[0045] A phase matching equation generation module is used to obtain a multi-wavelength dispersion-corrected non-collinear phase matching equation of the pump light, the signal light and the idler light in the crystal according to the refractive index and the multi-wavelength dispersion-corrected non-collinear phase matching formula;

[0046] An optimal parameter search module, used to search the multi-wavelength dispersion correction non-collinear phase matching equation by a particle swarm optimization algorithm to obtain the optimal non-collinear angle and crystal parameters;

[0047] The optical parametric laser amplifier system preparation module is used to prepare the optical parametric laser amplifier system according to the optimal non-collinear angle and crystal parameters, so as to achieve a high-efficiency optical parametric amplification effect under preset wavelength and angle conditions.

[0048] According to another aspect of the present invention, there is provided a computing device, comprising: a processor, a memory, a communication interface and a communication bus, wherein the processor, the memory and the communication interface communicate with each other via the communication bus;

[0049] According to the scheme provided by the present invention, the refractive index of the pump light, signal light and idler light in the crystal is calculated according to the high-order approximate dispersion equation of the Sellmeier equation and the nonlinear crystal parameters; wherein the nonlinear crystal parameters at least include the Sellmeier coefficient, the crystal temperature and the wavelength of the pump light, signal light and idler light; according to the refractive index and the multi-wavelength dispersion correction non-collinear phase matching formula, the multi-wavelength dispersion correction non-collinear phase matching equation of the pump light, signal light and idler light in the crystal is obtained; the multi-wavelength dispersion correction non-collinear phase matching equation is searched by the particle swarm optimization algorithm to obtain the optimal non-collinear angle and crystal parameters; according to the optimal non-collinear angle and crystal parameters, an optical parametric laser amplifier system is prepared to achieve an efficient optical parametric amplification effect under preset wavelength and angle conditions. The present invention adopts the high-order approximate dispersion equation of the Sellmeier equation, combined with the nonlinear crystal parameters, to further accurately calculate the refractive index of the pump light, signal light and idler light in the crystal. Based on the calculated refractive index, the multi-wavelength dispersion-corrected non-collinear phase matching formula is used to generate the multi-wavelength dispersion-corrected non-collinear phase matching equations for pump light, signal light and idler light in the crystal, ensuring that the phases between light waves can be accurately matched under different wavelengths and dispersion conditions, thereby improving the efficiency of optical parametric amplification. The particle swarm optimization algorithm is used to search the multi-wavelength dispersion-corrected non-collinear phase matching equations to find the optimal non-collinear angle and crystal parameters, ensuring that the obtained parameter combination can further maximize the effect of optical parametric amplification. The optical parametric laser amplifier system prepared according to the optimal non-collinear angle and crystal parameters achieves efficient optical parametric amplification effect under preset wavelength and angle conditions, which not only improves the output power of the laser, but also maintains the high-quality characteristics of the laser beam (such as pulse width, line width, polarization, etc.), while reducing the phase mismatch and energy loss in the optical parametric amplification process, thereby enhancing the stability and reliability of the system.

[0050] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention, it can be implemented according to the contents of the specification. In order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present invention. Moreover, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0052] Figure 1 A schematic flow chart showing a method for preparing an optical parametric laser amplifier according to an embodiment of the present invention is shown;

[0053] Figure 2 A schematic diagram showing a framework of an optical parametric laser amplifier manufacturing device according to an embodiment of the present invention;

[0054] Figure 3 A schematic diagram of the structure of a computing device according to an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0055] The exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided in order to enable a more thorough understanding of the present invention and to enable the scope of the present invention to be fully communicated to those skilled in the art.

[0056] Figure 1 FIG. 1 is a flow chart of a method for preparing an optical parametric laser amplifier according to an embodiment of the present invention. Specifically, Figure 1 As shown, the following steps are included:

[0057] Step S101, calculating the refractive index of the pump light, the signal light and the idler light in the crystal according to the high-order approximate dispersion equation of the Sellmeier equation and the nonlinear crystal parameters; wherein the nonlinear crystal parameters at least include the Sellmeier coefficient, the crystal temperature and the wavelengths of the pump light, the signal light and the idler light.

[0058] In this embodiment, the Sellmeier equation can accurately describe the dispersion characteristics of materials in a wide wavelength range through its high-order approximation. By adjusting the Sellmeier coefficient and temperature effect, the light propagation characteristics of various nonlinear crystals and various wavelengths can be calculated to optimize the performance of the optical parametric amplifier.

[0059] Specifically, the calculation formula of the refractive index is:

[0060]

[0061] The calculation formula of the refractive index of the signal light in the crystal is:

[0062]

[0063] The calculation formula of the refractive index of the idler light in the crystal is:

[0064]

[0065] Among them, λ p ,λ s ,λ i are the wavelengths of pump light, signal light and idler light respectively; T is the temperature of the crystal; Bi (T), C i (T) is the coefficient of the Sellmeier equation; m is the number of terms in the Sellmeier equation; n p , n s , n i are the refractive indices of pump light, signal light and idler light in the crystal respectively; α, β, γ are power term parameters; D j (T) is the higher-order dispersion coefficient; n is the number of higher-order terms.

[0066] In this embodiment, by introducing high-order dispersion terms and power term parameters, the dispersion behavior of light waves in nonlinear crystals can be described more accurately, especially in a wide wavelength range. The Sellmeier coefficient and high-order dispersion coefficient make the calculation results close to the actual working environment and improve the reliability of the design.

[0067] Step S102, obtaining a multi-wavelength dispersion corrected non-collinear phase matching equation of the pump light, the signal light and the idler light in the crystal according to the refractive index and the multi-wavelength dispersion corrected non-collinear phase matching formula.

[0068] The multi-wavelength dispersion-corrected non-collinear phase matching equation is based on the principles of momentum conservation and energy conservation, including the wave vector, refractive index, non-collinear angle, and crystal parameters of the light wave. The multi-wavelength dispersion-corrected non-collinear phase matching equation introduces the dispersion effect of pump light, signal light, and idler light at different wavelengths, which can accurately describe the interaction of light waves in nonlinear crystals and improve the accuracy of phase matching. This equation is applicable to light waves in a wide wavelength range and can realize optical parametric amplification or frequency conversion of multiple wavelengths in the same crystal. By solving the multi-wavelength dispersion-corrected non-collinear phase matching equation, the optimal non-collinear angle and crystal parameters are found, thereby optimizing the performance of the optical parametric amplifier, such as improving the conversion efficiency.

[0069] In this embodiment, the multi-wavelength dispersion correction non-collinear phase matching equation is:

[0070]

[0071] Among them, n p (λ p ,T) is the pump light at wavelength λ p and the refractive index at temperature T; n s (λ s ,T) is the signal light at wavelength λ s and the refractive index at temperature T; n i (λ i ,T) is the idler light at wavelength λ i and the refractive index at temperature T; is the pump light wave vector The unit direction component of ; is the signal light wave vector The unit direction component of ; Idle frequency wave vector The unit direction component of G x , G y , G z is the crystal reciprocal lattice vector Components of the signal light wave vector is a function of refractive index and wavelength,

[0072] The multi-wavelength dispersion-corrected non-collinear phase matching equation contains multiple unknowns and needs to be solved by numerical methods (such as particle swarm optimization algorithm, genetic algorithm, etc.) to find the optimal non-collinear angle and crystal parameters that meet the phase matching conditions.

[0073] Step S103, searching the multi-wavelength dispersion correction non-collinear phase matching equation by using a particle swarm optimization algorithm to obtain the optimal non-collinear angle and crystal parameters.

[0074] Particle Swarm Optimization (PSO) is an optimization technology based on swarm intelligence, which simulates the foraging behavior of bird flocks to find the optimal solution to the problem. When searching for the optimal non-collinear angle and crystal parameters of the multi-wavelength dispersion correction non-collinear phase matching equation through the particle swarm optimization algorithm (PSO), the physical problem can be converted into an optimization problem.

[0075] Specifically, determining optimization target variables, the target variables include non-collinear angles and crystal parameters; wherein the non-collinear angles include the angle between the signal light and the pump light and the angle between the idler light and the pump light, and the crystal parameters include temperature, crystal length, and cutting angle;

[0076] According to the objective function of the negative square value of the phase mismatch, the phase mismatch is minimized to achieve efficient nonlinear interaction; wherein the phase mismatch is obtained by subtracting the left side from the right side of the non-collinear phase matching equation;

[0077] A group of particles are randomly generated, and the squared negative value of the phase mismatch of each particle is evaluated; wherein each particle represents a set of non-collinear angles and crystal parameters;

[0078] For each particle, if the objective function value of the current position is better than the objective function value of its historical optimal position, its individual optimal solution is updated;

[0079] Among the individual optimal solutions of all particles, find the global optimal solution, that is, the particle with the largest objective function value;

[0080] Update the particle's speed and position based on the individual optimal solution, the global optimal solution, and the particle's current speed and position.

[0081] In this embodiment, the formula for updating the speed and position of the particle is:

[0082] v id t+1=w·v id t+c1·r1·(p id -x id t)+c2·r2·(p g -x id t)

[0083]

[0084] Among them, v id t and x id t is the velocity and position of particle i in the dth dimension and the tth generation, respectively, w is the inertia weight, c1 and c2 are learning factors, r1 and r2 are random numbers in the interval [0,1], p id is the individual optimal solution of particle i, p g It is the global optimal solution.

[0085] Optionally, since there may be multiple optimal solutions or local optimal solutions, the probability of finding the global optimal solution is increased by running the PSO algorithm multiple times.

[0086] In an optional manner, the particle swarm optimization algorithm introduces a dynamic inertia weight. During the iteration process, the value of the inertia weight is dynamically adjusted so that a larger value is used for global search in the early stage of the search and a smaller value is gradually used for local fine search in the later stage of the search, thereby balancing the global search capability and local convergence capability of the algorithm.

[0087] When a particle exceeds the preset search space boundary during the iteration process, it is pulled back into the search space by reflection or re-random generation to ensure the continuity of the search;

[0088] The maximum number of iterations and convergence conditions are set, and the iteration is stopped when any condition is met, and the optimal non-collinear angle and crystal parameters are output; wherein the convergence condition is that the change in the objective function value for consecutive preset generations is less than a preset threshold.

[0089] Step S104, preparing an optical parametric laser amplifier system according to the optimal non-collinear angle and crystal parameters, so as to achieve a highly efficient optical parametric amplification effect under preset wavelength and angle conditions.

[0090] Specifically, nonlinear crystals are selected according to the requirements of optical parametric amplification;

[0091] Process the crystal according to the cutting angle and length, and stabilize the crystal at the operating temperature to ensure that it meets the phase matching conditions;

[0092] The optical paths of the pump light and the signal light are adjusted so that they are incident on the nonlinear crystal at an optimal non-collinear angle.

[0093] Further, according to the optimal non-collinear angle and crystal parameters, a pump light source, an optical lens, a reflector and a filter are selected and assembled to form a stable optical path system;

[0094] Fix the nonlinear crystal in a temperature control device, and control the temperature of the crystal through the temperature control device to ensure that it maintains the optimal working temperature during the experiment;

[0095] After the optical path system is built, the optical paths of the pump light, signal light and idler light are adjusted, the non-collinear angle is optimized, and the position and temperature of the crystal are fine-tuned to achieve the best phase matching and optical parametric amplification effect.

[0096] According to the scheme provided by the present invention, the refractive index of the pump light, signal light and idler light in the crystal is calculated according to the high-order approximate dispersion equation of the Sellmeier equation and the nonlinear crystal parameters; wherein the nonlinear crystal parameters at least include the Sellmeier coefficient, the crystal temperature and the wavelength of the pump light, signal light and idler light; according to the refractive index and the multi-wavelength dispersion correction non-collinear phase matching formula, the multi-wavelength dispersion correction non-collinear phase matching equation of the pump light, signal light and idler light in the crystal is obtained; the multi-wavelength dispersion correction non-collinear phase matching equation is searched by the particle swarm optimization algorithm to obtain the optimal non-collinear angle and crystal parameters; according to the optimal non-collinear angle and crystal parameters, an optical parametric laser amplifier system is prepared to achieve an efficient optical parametric amplification effect under preset wavelength and angle conditions. The present invention adopts the high-order approximate dispersion equation of the Sellmeier equation, combined with the nonlinear crystal parameters, to further accurately calculate the refractive index of the pump light, signal light and idler light in the crystal. Based on the calculated refractive index, the multi-wavelength dispersion-corrected non-collinear phase matching formula is used to generate the multi-wavelength dispersion-corrected non-collinear phase matching equations for pump light, signal light and idler light in the crystal, ensuring that the phases between light waves can be accurately matched under different wavelengths and dispersion conditions, thereby improving the efficiency of optical parametric amplification. The particle swarm optimization algorithm is used to search the multi-wavelength dispersion-corrected non-collinear phase matching equations to find the optimal non-collinear angle and crystal parameters, ensuring that the obtained parameter combination can further maximize the effect of optical parametric amplification. The optical parametric laser amplifier system prepared according to the optimal non-collinear angle and crystal parameters achieves efficient optical parametric amplification effect under preset wavelength and angle conditions, which not only improves the output power of the laser, but also maintains the high-quality characteristics of the laser beam (such as pulse width, line width, polarization, etc.), while reducing the phase mismatch and energy loss in the optical parametric amplification process, thereby enhancing the stability and reliability of the system.

[0097] Figure 2 The schematic diagram of the structure of the optical parametric laser amplifier manufacturing device of the embodiment of the present invention is shown. The optical parametric laser amplifier manufacturing device comprises: a refractive index calculation module 210, a phase matching equation generation module 220, an optimal parameter search module 230 and an optical parametric laser amplifier system manufacturing module 240.

[0098] The refractive index calculation module 210 is used to calculate the refractive index of the pump light, the signal light and the idler light in the crystal according to the high-order approximate dispersion equation of the Sellmeier equation and the nonlinear crystal parameters; wherein the nonlinear crystal parameters at least include the Sellmeier coefficient, the crystal temperature and the wavelengths of the pump light, the signal light and the idler light;

[0099] The phase matching equation generating module 220 is used to obtain the multi-wavelength dispersion-corrected non-collinear phase matching equation of the pump light, the signal light and the idler light in the crystal according to the refractive index and the multi-wavelength dispersion-corrected non-collinear phase matching formula;

[0100] The optimal parameter search module 230 is used to search the multi-wavelength dispersion correction non-collinear phase matching equation by particle swarm optimization algorithm to obtain the optimal non-collinear angle and crystal parameters;

[0101] The optical parametric laser amplifier system preparation module 240 is used to prepare an optical parametric laser amplifier system according to the optimal non-collinear angle and crystal parameters, so as to achieve an efficient optical parametric amplification effect under preset wavelength and angle conditions.

[0102] In an optional manner, the calculation formula of the refractive index is:

[0103]

[0104] The calculation formula of the refractive index of the signal light in the crystal is:

[0105]

[0106] The calculation formula of the refractive index of the idler light in the crystal is:

[0107]

[0108] Among them, λ p ,λ s ,λ i are the wavelengths of pump light, signal light and idler light respectively; T is the temperature of the crystal; B i (T), C i (T) is the coefficient of the Sellmeier equation; m is the number of terms in the Sellmeier equation; n p , n s , n i are the refractive indices of pump light, signal light and idler light in the crystal respectively; α, β, γ are power term parameters; D j (T) is the higher-order dispersion coefficient; n is the number of higher-order terms.

[0109] In an optional manner, the multi-wavelength dispersion-corrected non-collinear phase matching equation is:

[0110]

[0111] Among them, n p (λ p ,T) is the pump light at wavelength λ p and the refractive index at temperature T; ns (λ s ,T) is the signal light at wavelength λ s and the refractive index at temperature T; n i (λ i ,T) is the idler light at wavelength λ i and the refractive index at temperature T; is the pump light wave vector The unit direction component of ; is the signal light wave vector The unit direction component of ; Idle frequency wave vector The unit direction component of G x , G y , G z is the crystal reciprocal lattice vector The amount.

[0112] In an optional manner, searching the multi-wavelength dispersion correction non-collinear phase matching equation by a particle swarm optimization algorithm to obtain the optimal non-collinear angle and crystal parameters further includes:

[0113] Determine optimization target variables, the target variables include non-collinear angles and crystal parameters; wherein the non-collinear angles include the angle between the signal light and the pump light and the angle between the idler light and the pump light, and the crystal parameters include temperature, crystal length, and cutting angle;

[0114] According to the objective function of the negative square value of the phase mismatch, the phase mismatch is minimized to achieve efficient nonlinear interaction; wherein the phase mismatch is obtained by subtracting the left side from the right side of the non-collinear phase matching equation;

[0115] A group of particles are randomly generated, and the squared negative value of the phase mismatch of each particle is evaluated; wherein each particle represents a set of non-collinear angles and crystal parameters;

[0116] For each particle, if the objective function value of the current position is better than the objective function value of its historical optimal position, its individual optimal solution is updated;

[0117] Among the individual optimal solutions of all particles, find the global optimal solution, that is, the particle with the largest objective function value;

[0118] Update the particle's speed and position based on the individual optimal solution, the global optimal solution, and the particle's current speed and position.

[0119] In an optional manner, the formula for updating the velocity and position of the particle is:

[0120] v id t+1=w·v id t+c1·r1·(pid -x id t)+c2·r2·(p g -x id t)

[0121]

[0122] Among them, v id t and x id t is the velocity and position of particle i in the dth dimension and the tth generation, w is the inertia weight, c1 and c2 are learning factors, r1 and r2 are random numbers, p id is the individual optimal solution of particle i, p g It is the global optimal solution.

[0123] In an optional manner, the preparing an optical parametric laser amplifier system according to the optimal non-collinear angle and crystal parameters further comprises:

[0124] Select nonlinear crystals based on the requirements of optical parametric amplification;

[0125] Process the crystal according to the cutting angle and length, and stabilize the crystal at the operating temperature to ensure that it meets the phase matching conditions;

[0126] The optical paths of the pump light and the signal light are adjusted so that they are incident on the nonlinear crystal at an optimal non-collinear angle.

[0127] In an optional manner, the method further includes:

[0128] The particle swarm optimization algorithm introduces a dynamic inertia weight. During the iteration process, the value of the inertia weight is dynamically adjusted so that it performs a global search with a larger value in the early stage of the search and gradually decreases in the later stage of the search to perform a local fine search, thereby balancing the global search ability and local convergence ability of the algorithm;

[0129] When a particle exceeds the preset search space boundary during the iteration process, it is pulled back into the search space by reflection or re-random generation to ensure the continuity of the search;

[0130] The maximum number of iterations and convergence conditions are set, and the iteration is stopped when any condition is met, and the optimal non-collinear angle and crystal parameters are output; wherein the convergence condition is that the change in the objective function value for consecutive preset generations is less than a preset threshold.

[0131] In an optional manner, the preparation of the optical parametric laser amplifier system further comprises:

[0132] According to the optimal non-collinear angle and crystal parameters, the pump light source, optical lens, reflector and filter are selected and assembled to form a stable optical path system;

[0133] Fix the nonlinear crystal in a temperature control device, and control the temperature of the crystal through the temperature control device to ensure that it maintains the optimal working temperature during the experiment;

[0134] After the optical path system is built, the optical paths of the pump light, signal light and idler light are adjusted, the non-collinear angle is optimized, and the position and temperature of the crystal are fine-tuned to achieve the best phase matching and optical parametric amplification effect.

[0135] Figure 3 A schematic diagram of the structure of an embodiment of a computing device of the present invention is shown. The specific embodiment of the present invention does not limit the specific implementation of the computing device.

[0136] like Figure 3 As shown, the computing device may include: a processor (processor) 302 , a communication interface (Communications Interface) 304 , a memory (memory) 306 , and a communication bus 308 .

[0137] The processor 302, the communication interface 304, and the memory 306 communicate with each other via the communication bus 308. The communication interface 304 is used to communicate with other devices such as a client or other server network elements. The processor 302 is used to execute the program 310, which can specifically execute the relevant steps in the above-mentioned optical parametric laser amplifier preparation method embodiment.

[0138] Specifically, the program 310 may include program codes, which include computer operation instructions.

[0139] The processor 302 may be a central processing unit (CPU), or an application specific integrated circuit (ASIC), or one or more integrated circuits configured to implement the embodiments of the present invention. The one or more processors included in the computing device may be processors of the same type, such as one or more CPUs; or processors of different types, such as one or more CPUs and one or more ASICs.

[0140] The memory 306 is used to store the program 310. The memory 306 may include a high-speed RAM memory, and may also include a non-volatile memory (non-volatile memory), such as at least one disk memory.

[0141] According to the scheme provided by the present invention, the refractive index of the pump light, signal light and idler light in the crystal is calculated according to the high-order approximate dispersion equation of the Sellmeier equation and the nonlinear crystal parameters; wherein the nonlinear crystal parameters at least include the Sellmeier coefficient, the crystal temperature and the wavelength of the pump light, signal light and idler light; according to the refractive index and the multi-wavelength dispersion correction non-collinear phase matching formula, the multi-wavelength dispersion correction non-collinear phase matching equation of the pump light, signal light and idler light in the crystal is obtained; the multi-wavelength dispersion correction non-collinear phase matching equation is searched by the particle swarm optimization algorithm to obtain the optimal non-collinear angle and crystal parameters; according to the optimal non-collinear angle and crystal parameters, an optical parametric laser amplifier system is prepared to achieve an efficient optical parametric amplification effect under preset wavelength and angle conditions. The present invention adopts the high-order approximate dispersion equation of the Sellmeier equation, combined with the nonlinear crystal parameters, to further accurately calculate the refractive index of the pump light, signal light and idler light in the crystal. Based on the calculated refractive index, the multi-wavelength dispersion-corrected non-collinear phase matching formula is used to generate the multi-wavelength dispersion-corrected non-collinear phase matching equations for pump light, signal light and idler light in the crystal, ensuring that the phases between light waves can be accurately matched under different wavelengths and dispersion conditions, thereby improving the efficiency of optical parametric amplification. The particle swarm optimization algorithm is used to search the multi-wavelength dispersion-corrected non-collinear phase matching equations to find the optimal non-collinear angle and crystal parameters, ensuring that the obtained parameter combination can further maximize the effect of optical parametric amplification. The optical parametric laser amplifier system prepared according to the optimal non-collinear angle and crystal parameters achieves efficient optical parametric amplification effect under preset wavelength and angle conditions, which not only improves the output power of the laser, but also maintains the high-quality characteristics of the laser beam (such as pulse width, line width, polarization, etc.), while reducing the phase mismatch and energy loss in the optical parametric amplification process, thereby enhancing the stability and reliability of the system.

[0142] Those skilled in the art will appreciate that the modules in the devices in the embodiments can be adaptively changed and set in one or more devices different from the embodiments. The modules or units or components in the embodiments can be combined into one module or unit or component, and in addition they can be divided into multiple submodules or subunits or subcomponents. Except that at least some of such features and / or processes or units are mutually exclusive, all features disclosed in this specification (including the accompanying claims, abstracts and drawings) and all processes or units of any method or device disclosed in this manner can be combined in any combination. Unless otherwise explicitly stated, each feature disclosed in this specification (including the accompanying claims, abstracts and drawings) can be replaced by an alternative feature that provides the same, equivalent or similar purpose. In addition, those skilled in the art will appreciate that although some embodiments herein include certain features included in other embodiments but not other features, the combination of features of different embodiments means being within the scope of the present invention and forming different embodiments. For example, in the following claims, any one of the claimed embodiments can be used in any combination. The present invention can be implemented by hardware including several different elements and by appropriately programmed computers. In a unit claim that lists several means, several of these means may be embodied by the same hardware item. The steps in the above embodiments should not be understood as limiting the execution order unless otherwise specified.

Claims

1. A method for preparing an optical parametric laser amplifier, characterized in that: include: Calculating the refractive indexes of the pump light, the signal light and the idler light in the crystal according to the high-order approximate dispersion equation of the Sellmeier equation and the nonlinear crystal parameters; wherein the nonlinear crystal parameters at least include the Sellmeier coefficient, the crystal temperature and the wavelengths of the pump light, the signal light and the idler light; According to the refractive index and the multi-wavelength dispersion correction non-collinear phase matching formula, a multi-wavelength dispersion correction non-collinear phase matching equation of the pump light, the signal light and the idler light in the crystal is obtained; Searching the multi-wavelength dispersion correction non-collinear phase matching equation by a particle swarm optimization algorithm to obtain the optimal non-collinear angle and crystal parameters; According to the optimal non-collinear angle and crystal parameters, an optical parametric laser amplifier system is prepared to achieve a highly efficient optical parametric amplification effect under preset wavelength and angle conditions.

2. The method for preparing an optical parametric laser amplifier according to claim 1, characterized in that: The calculation formula of the refractive index is: The calculation formula of the refractive index of the signal light in the crystal is: The calculation formula of the refractive index of the idler light in the crystal is: Among them, λ p ,λ s ,λ i are the wavelengths of pump light, signal light and idler light respectively; T is the temperature of the crystal; B i (T), C i (T) is the coefficient of the Sellmeier equation; m is the number of terms in the Sellmeier equation; n p , n s , n i are the refractive indices of pump light, signal light and idler light in the crystal respectively; α, β, γ are power term parameters; D j (T) is the higher-order dispersion coefficient; n is the number of higher-order terms.

3. The method for preparing an optical parametric laser amplifier according to claim 2, characterized in that: The multi-wavelength dispersion-corrected non-collinear phase matching equation is: Among them, n p (λ p ,T) is the pump light at wavelength λ p and the refractive index at temperature T; n s (λ s ,T) is the signal light at wavelength λ s and the refractive index at temperature T; n i (λ i ,T) is the idler light at wavelength λ i and the refractive index at temperature T; is the pump light wave vector The unit direction component of ; is the signal light wave vector The unit direction component of ; Idle frequency wave vector The unit direction component of G x , G y , G z is the crystal reciprocal lattice vector The amount.

4. The method for preparing an optical parametric laser amplifier according to claim 1, characterized in that: The step of searching the multi-wavelength dispersion correction non-collinear phase matching equation by a particle swarm optimization algorithm to obtain the optimal non-collinear angle and crystal parameters further comprises: Determine optimization target variables, the target variables include non-collinear angles and crystal parameters; wherein the non-collinear angles include the angle between the signal light and the pump light and the angle between the idler light and the pump light, and the crystal parameters include temperature, crystal length, and cutting angle; According to the objective function of the negative square value of the phase mismatch, the phase mismatch is minimized to achieve efficient nonlinear interaction; wherein the phase mismatch is obtained by subtracting the left side from the right side of the non-collinear phase matching equation; A group of particles are randomly generated, and the squared negative value of the phase mismatch of each particle is evaluated; wherein each particle represents a set of non-collinear angles and crystal parameters; For each particle, if the objective function value of the current position is better than the objective function value of its historical optimal position, its individual optimal solution is updated; Among the individual optimal solutions of all particles, find the global optimal solution, that is, the particle with the largest objective function value; Update the particle's speed and position based on the individual optimal solution, the global optimal solution, and the particle's current speed and position.

5. The method for preparing an optical parametric laser amplifier according to claim 4, characterized in that: The formula for updating the particle's velocity and position is: v id t+1=w·v id t+c1·r1·(p id -x id t)+c2·r2·(p g -x id t) Among them, v id t and x id t is the velocity and position of particle i in the dth dimension and the tth generation, w is the inertia weight, c1 and c2 are learning factors, r1 and r2 are random numbers, p id is the individual optimal solution of particle i, p g It is the global optimal solution.

6. The method for preparing an optical parametric laser amplifier according to claim 1, characterized in that: The step of preparing an optical parametric laser amplifier system according to the optimal non-collinear angle and crystal parameters further comprises: Select nonlinear crystals based on the requirements of optical parametric amplification; Process the crystal according to the cutting angle and length, and stabilize the crystal at the operating temperature to ensure that it meets the phase matching conditions; The optical paths of the pump light and the signal light are adjusted so that they are incident on the nonlinear crystal at an optimal non-collinear angle.

7. The method for preparing an optical parametric laser amplifier according to claim 4 or 5, characterized in that: The method further comprises: The particle swarm optimization algorithm introduces a dynamic inertia weight. During the iteration process, the value of the inertia weight is dynamically adjusted so that it performs a global search with a larger value in the early stage of the search and gradually decreases in the later stage of the search to perform a local fine search, thereby balancing the global search ability and local convergence ability of the algorithm; When a particle exceeds the preset search space boundary during the iteration process, it is pulled back into the search space by reflection or re-random generation to ensure the continuity of the search; The maximum number of iterations and convergence conditions are set, and the iteration is stopped when any condition is met, and the optimal non-collinear angle and crystal parameters are output; wherein the convergence condition is that the change in the objective function value for consecutive preset generations is less than a preset threshold.

8. The method for preparing an optical parametric laser amplifier according to claim 6, characterized in that: The preparation of the optical parametric laser amplifier system further comprises: According to the optimal non-collinear angle and crystal parameters, the pump light source, optical lens, reflector and filter are selected and assembled to form a stable optical path system; Fix the nonlinear crystal in a temperature control device, and control the temperature of the crystal through the temperature control device to ensure that it maintains the optimal working temperature during the experiment; After the optical path system is built, the optical paths of the pump light, signal light and idler light are adjusted, the non-collinear angle is optimized, and the position and temperature of the crystal are fine-tuned to achieve the best phase matching and optical parametric amplification effect.

9. An optical parametric laser amplifier manufacturing device, characterized in that: include: A refractive index calculation module, used to calculate the refractive index of the pump light, the signal light and the idler light in the crystal according to the high-order approximate dispersion equation of the Sellmeier equation and the nonlinear crystal parameters; wherein the nonlinear crystal parameters at least include the Sellmeier coefficient, the crystal temperature and the wavelengths of the pump light, the signal light and the idler light; A phase matching equation generation module is used to obtain a multi-wavelength dispersion-corrected non-collinear phase matching equation of the pump light, the signal light and the idler light in the crystal according to the refractive index and the multi-wavelength dispersion-corrected non-collinear phase matching formula; An optimal parameter search module, used to search the multi-wavelength dispersion correction non-collinear phase matching equation by a particle swarm optimization algorithm to obtain the optimal non-collinear angle and crystal parameters; The optical parametric laser amplifier system preparation module is used to prepare the optical parametric laser amplifier system according to the optimal non-collinear angle and crystal parameters, so as to achieve a high-efficiency optical parametric amplification effect under preset wavelength and angle conditions.

10. A computing device comprising: A processor, a memory, a communication interface and a communication bus, wherein the processor, the memory and the communication interface communicate with each other via the communication bus; The memory is used to store at least one executable instruction, and the executable instruction enables the processor to execute operations corresponding to the above-mentioned optical parametric laser amplifier preparation method.

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