Simulation method and device for laser processing of nanoparticles

Abstract

The present invention discloses a simulation method and device for laser processing of nanoparticles, which is applied to the field of laser precision processing. By simulating the process of laser processing of nanoparticles, the method can use the simulation parameters of each first moment as the simulation result. This achieves high-time resolution monitoring of the interaction mechanism between nanoparticles and lasers while eliminating the need to obtain the interaction mechanism between nanoparticles and lasers through experiments, saving time and effort and being highly efficient. Furthermore, since the photoelectric field is affected by the morphology of the nanoparticles, the multi-physics field in the simulation model at the second moment obtained based on the photoelectric field in the simulation model at the first moment can take into account the photoelectric field changes caused by the morphological changes of the nanoparticles under laser irradiation, making the calculation results more in line with the actual situation.

Description

Technical Field

[0001] The present application relates to the field of laser precision processing, and specifically to a simulation method and device for laser processing of nanoparticles. Background Art

[0002] Flexible conductive devices are fundamental components in flexible electronic applications, and the patterning of liquid metal is key to their preparation. Ultrasonic treatment of liquid metal to produce nanoparticles can overcome the surface energy of the liquid metal. The nanoparticles can be liquid metal nanoparticles. In addition, lasers are used to provide photothermal energy to the nanoparticles, allowing them to connect with each other to form conductive pathways. Since laser processing of nanoparticles is a multi-physics process involving light, heat, and force, it is currently necessary to study the interaction mechanism between nanoparticles and lasers to obtain optimal experimental parameters. These experimental parameters can include laser parameters and the type of nanoparticles.

[0003] In related technologies, the interaction mechanism between lasers and nanoparticles is usually studied through experiments. However, this process often requires the use of expensive experimental equipment such as high-speed cameras and electron microscopes, and the need to frequently change experimental parameters. This method is time-consuming, labor-intensive, and inefficient. Summary of the Invention

[0004] The present invention provides a simulation method and device for laser processing nanoparticles, which can solve the problem that the method of obtaining the interaction mechanism between laser and nanoparticles through experiments in related technologies is time-consuming, labor-intensive, and inefficient. The technical solution includes:

[0005] In one aspect, a simulation method for laser processing of nanoparticles is provided, the method comprising:

[0006] During the simulation of laser processing of nanoparticles based on the simulation model, an iterative process is repeatedly performed based on the simulation model until an iteration termination condition is detected. The iterative process includes:

[0007] Based on the level set physical field in the simulation model at the first moment, the photoelectric field in the simulation model at the first moment is obtained, and based on the photoelectric field in the simulation model at the first moment, the multi-physical field in the simulation model at the second moment is obtained; the multi-physical field includes at least a thermal field, a fluid field, and a level set physical field, the second moment is later than the first moment, and the second moment and the first moment are separated by a time step;

[0008] If the iteration termination condition is not detected, the first moment and the second moment are updated; wherein the updated first moment is the second moment before the update, and the interval between the updated second moment and the second moment before the update is the time step;

[0009] If an iteration termination condition is detected, the simulation parameters at each first moment are used as simulation results, and the simulation parameters at least include multiple physical fields.

[0010] Optionally, if the morphology of the nanoparticles changes dramatically at the first moment, the time step is the first time step;

[0011] If the morphological change of the nanoparticles at the first moment is mild, the time step is the second time step;

[0012] The first time step is smaller than the second time step.

[0013] Optionally, the method further includes:

[0014] Acquire multiple changing velocities of the boundary of the nanoparticle at a first moment;

[0015] If the maximum value of the absolute values ​​of the multiple change speeds is greater than or equal to the speed threshold, it is determined that the morphology of the nanoparticles changes dramatically;

[0016] If the maximum value of the absolute values ​​of the multiple change speeds is less than the speed threshold, it is determined that the morphology change of the nanoparticles is moderate.

[0017] Optionally, the simulation model includes a plurality of grids; after obtaining the multi-physical field in the simulation model at the second moment based on the optical and electrical field in the simulation model at the first moment, the method further includes:

[0018] If the maximum value of the level set physics across multiple grids is less than the level set physics threshold, then it is determined that an iteration termination condition has been detected.

[0019] Optionally, obtaining the optical and electrical field in the simulation model at the first moment based on the level set physical field in the simulation model at the first moment includes:

[0020] Obtaining the relative dielectric constant of the nanoparticles at the first moment based on the level set physical field in the simulation model at the first moment;

[0021] Based on the relative dielectric constant at the first moment and the optical field calculation model, the optical field in the simulation model at the first moment is obtained.

[0022] Optionally, obtaining the relative dielectric constant of the nanoparticles at the first moment based on the level set physical field in the simulation model at the first moment includes:

[0023] If the level set physical field is less than a preset value, the relative dielectric constant of the nanoparticle is a first relative dielectric constant;

[0024] If the level set physical field is greater than or equal to the preset value, the relative permittivity is the second relative permittivity;

[0025] The first relative permittivity is different from the second relative permittivity.

[0026] Optionally, the first relative dielectric constant is the relative dielectric constant when the nanoparticles are gas, and the second relative dielectric constant is the relative dielectric constant when the nanoparticles are non-gas.

[0027] On the other hand, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the simulation method for laser processing nanoparticles described in the above aspects is implemented.

[0028] On the other hand, a computer device is provided, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the simulation method for laser processing nanoparticles in the above aspect is implemented.

[0029] In another aspect, a simulation device for laser processing nanoparticles is provided, the device comprising:

[0030] The iterative process execution module is used to repeatedly execute the iterative process based on the simulation model during the process of simulating laser processing of nanoparticles based on the simulation model until an iteration termination condition is detected; wherein the iterative process includes:

[0031] Based on the level set physical field in the simulation model at the first moment, the photoelectric field in the simulation model at the first moment is obtained, and based on the photoelectric field in the simulation model at the first moment, the multi-physical field in the simulation model at the second moment is obtained; wherein the multi-physical field includes at least a thermal field, a fluid field, and a level set physical field, the second moment is later than the first moment, and the second moment and the first moment are separated by a time step;

[0032] If the iteration termination condition is not detected, the first moment and the second moment are updated; wherein the updated first moment is the second moment before the update, and the interval between the updated second moment and the second moment before the update is the time step;

[0033] The determination module is used to use the simulation parameters at each first moment as the simulation result if an iteration termination condition is detected, and the simulation parameters at least include multiple physical fields.

[0034] In summary, the embodiments of the present application provide a simulation method and device for laser processing nanoparticles, which can obtain the photoelectric field in the simulation model at the first moment based on the level set physical field in the simulation model at the first moment, and obtain the multi-physics field in the simulation model at the second moment based on the photoelectric field in the simulation model at the first moment. If the iteration termination condition is detected, the simulation parameters of each first moment can be used as the simulation result. This achieves high time resolution monitoring of the interaction mechanism between nanoparticles and lasers while eliminating the need to obtain the interaction mechanism between nanoparticles and lasers through experiments, saving time and effort and being highly efficient. And because the photoelectric field is affected by the morphology of the nanoparticles, the multi-physics field in the simulation model at the second moment obtained based on the photoelectric field in the simulation model at the first moment can take into account the photoelectric field changes caused by the morphological changes of the nanoparticles under laser irradiation, so that the calculation results are more in line with the actual situation.

[0035] Additional aspects and advantages of the present invention will be set forth in part in the description which follows and, in part, will be obvious from the description which follows, or may be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 This is a flow chart of a simulation method for laser processing nanoparticles provided in an embodiment of the present application;

[0037] Figure 2 is a schematic diagram of laser processing of nanoparticles provided in an embodiment of the present application;

[0038] Figure 3 is a schematic diagram of a geometric model provided in an embodiment of the present application;

[0039] Figure 4 is a grid diagram of a geometric model provided in an embodiment of the present application;

[0040] Figure 5 This is a flowchart of an iterative process provided by an embodiment of the present application;

[0041] Figure 6 This is a schematic diagram of the volume fraction of nanoparticles at 0.2 nanoseconds (ns) provided in an embodiment of the present application;

[0042] Figure 7 This is a schematic diagram of the temperature distribution of nanoparticles at 0.2 ns provided in an embodiment of the present application;

[0043] Figure 8 Schematic diagram of the recoil pressure exerted on a nanoparticle at 0.2 ns, provided in an embodiment of the present application;

[0044] Figure 91 is a schematic diagram of the volume fraction of nanoparticles at 5 ns provided in an embodiment of the present application;

[0045] Figure 10 This is a schematic diagram of the temperature distribution of nanoparticles at 5 ns provided in an embodiment of the present application;

[0046] Figure 11 Schematic diagram of the recoil pressure on nanoparticles at 5 ns provided in an embodiment of the present application;

[0047] Figure 12 This is another schematic diagram of the volume fraction of nanoparticles at 0.2 ns provided in an embodiment of the present application;

[0048] Figure 13 This is another schematic diagram of the temperature distribution of nanoparticles at 0.2 ns provided in an embodiment of the present application;

[0049] Figure 14 Schematic diagram of another recoil pressure on nanoparticles at 0.2 ns provided in an embodiment of the present application;

[0050] Figure 15 1 is another schematic diagram of the volume fraction of nanoparticles at 5 ns provided in an embodiment of the present application;

[0051] Figure 16 This is another schematic diagram of the temperature distribution of nanoparticles at 5 ns provided in an embodiment of the present application;

[0052] Figure 17 Schematic diagram of another recoil pressure on nanoparticles at 5 ns provided in an embodiment of the present application;

[0053] Figure 18 This is a schematic diagram of the structure of a computer device provided in an embodiment of the present application;

[0054] Figure 19 This is a block diagram of a simulation device for laser processing nanoparticles provided in an embodiment of the present application. DETAILED DESCRIPTION

[0055] The following describes embodiments of the present invention in detail, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and are not to be construed as limiting the present invention.

[0056] Flexible conductive devices are fundamental components in flexible electronic applications. Liquid metals, such as gallium-based alloys, possess both excellent flexibility and conductivity, making them ideal materials for their fabrication. Patterning of liquid metals is crucial for their fabrication. However, the extremely high surface energy of liquid metals makes it difficult to wet flexible substrates. Ultrasonic treatment of liquid metal to produce nanoparticles can overcome this surface energy. However, the oxide layer on the surface of each nanoparticle isolates them from one another, preventing them from forming a conductive path. These nanoparticles can include liquid metal nanoparticles, gold nanoparticles, or silver nanoparticles.

[0057] Laser direct writing technology uses a high-energy focused spot to scan nanoparticles, thereby achieving the processing of liquid metal. It has the characteristics of wide applicability to liquid metals, high precision and good flexibility. In addition, laser direct writing technology has significant advantages in terms of patterning accuracy, process stability, processing efficiency and scalability for liquid metal. Therefore, laser direct writing technology is usually used to provide photothermal energy to nanoparticles, causing the nanoparticles to rupture due to the mismatch between the thermal expansion of the nanoparticles and their oxide layer, and then connecting the nanoparticles to form a conductive path.

[0058] Since laser processing of nanoparticles is a multi-physics process involving light, heat, and force, it is usually necessary to study the interaction mechanism between nanoparticles and lasers to obtain better experimental parameters. The experimental parameters can include laser parameters and the type of nanoparticles.

[0059] In related technologies, detailed studies of the interaction mechanism between lasers and nanoparticles are typically conducted experimentally. However, this approach often requires expensive experimental equipment such as high-speed cameras and electron microscopes, and requires frequent changes in experimental parameters. Therefore, experimental research alone is time-consuming and laborious, and it is impossible to fully understand the temperature field during processing and the morphological changes of liquid metal nanoparticles.

[0060] Furthermore, current laser processing simulation methods are suitable for simulating the laser processing of large workpieces (millimeter-scale and larger), but are not suitable for nanoparticles of nanometer size. For large workpieces, the heat source generated by laser irradiation can be considered a surface heat source on the workpiece surface. However, for nanoparticles of nanometer size, the heat source generated by laser irradiation is distributed throughout the nanoparticle and should be considered a volume heat source.

[0061] Furthermore, the light field distribution formed during laser irradiation determines the heat source of the nanoparticles, but current simulation methods are unable to calculate the changes in the light field distribution as the morphology of the liquid metal nanoparticles changes. The interaction between the nanoparticles and the light field under laser irradiation (this interaction includes scattering, absorption, surface plasmon oscillations, etc.) makes the light field distribution very sensitive to the morphology of the liquid metal nanoparticles. During the laser processing process, the morphology of the liquid metal nanoparticles continues to change significantly, and the light field distribution is affected by the morphology of the liquid metal nanoparticles, resulting in a significant change in the heat source distribution as the morphology of the liquid metal nanoparticles changes. Current simulation methods are too coarse in their simulation of the relevant processes, resulting in significant distortion when calculating the laser processing of nanoparticles.

[0062] To address the shortcomings of the prior art, embodiments of the present application provide a simulation method for laser processing of nanoparticles based on the level set method, using the finite element method to perform numerical calculations. In this method, a computer device, while repeatedly executing an iterative process based on a simulation model, can obtain the optical field (which can characterize the optical field distribution) within the simulation model at the first moment based on the level set physical field within the simulation model at the first moment, and can also obtain the multi-physics field within the simulation model at the second moment based on the optical field within the simulation model at the first moment. If the iteration termination condition is not detected, the second moment and the first moment are updated. If the iteration termination condition is detected, the simulation parameters at each first moment can be used as the simulation result, thereby obtaining the thermal field (i.e., temperature distribution), fluid field, and level set physical field (i.e., nanoparticle morphology) at each first moment during the laser processing of nanoparticles. This method enables high-temporal-resolution monitoring of the interaction mechanism between nanoparticles and laser light without the need for experimentally determining the interaction mechanism. Compared to related technologies, this method saves time and effort and is more efficient.

[0063] Moreover, since the photoelectric field is affected by the morphology of the nanoparticles, the multi-physics field in the simulation model at the second moment obtained based on the photoelectric field in the simulation model at the first moment can take into account the changes in the photoelectric field caused by the morphological changes of the nanoparticles under laser irradiation, making the calculation results more in line with the actual situation.

[0064] Furthermore, if the iteration termination condition is not detected, the second moment and the first moment are updated. Based on the level set physics field within the updated simulation model at the first moment, the optical and electrical fields within the updated simulation model at the first moment are obtained. That is, the transient results of the updated first moment are used to feed back the calculation of the optical and electrical fields, triggering a new round of optical and electrical field calculations. Subsequently, based on the optical and electrical fields within the updated simulation model at the first moment, the multi-physics fields within the updated simulation model at the second moment are obtained, and multiple iterations are performed until the iteration termination condition is detected. Thus, through a cyclic calculation method, the dynamic trajectory of the optical and electrical fields as they evolve with the nanoparticle morphology is fully captured, ensuring a high degree of consistency between the simulation results and the actual physical process.

[0065] Figure 1 This is a flow chart of a simulation method for laser processing nanoparticles provided in an embodiment of the present application. The simulation method can be applied to computer equipment. Figure 1 As shown, the method includes:

[0066] Step 101 : During the simulation of laser processing of nanoparticles based on the simulation model, an iterative process is repeatedly performed based on the simulation model until an iteration termination condition is detected.

[0067] After constructing the simulation model of laser processing nanoparticles, the computer device may repeatedly execute an iterative process based on the simulation model until an iteration termination condition is detected. The iterative process may include the following steps S1 to S3:

[0068] S1. Based on the level set physical field in the simulation model at the first moment, obtain the optical and electrical field in the simulation model at the first moment.

[0069] The computer device can obtain the optical and electrical field in the simulation model at the first moment based on the level set physical field in the simulation model at the first moment.

[0070] The optical field can represent the optical field distribution, and the level set field of the nanoparticles can represent the morphology of the nanoparticles. When the iterative process is first executed, the level set field in the simulation model at the first moment can be calculated based on the initial optical field.

[0071] S2. Based on the photoelectric field in the simulation model at the first moment, obtain the multi-physical field in the simulation model at the second moment.

[0072] After obtaining the optical and electrical fields within the simulation model at a first moment, the computer device can obtain the multi-physics fields within the simulation model at a second moment based on the optical and electrical fields within the simulation model at the first moment, where the second moment is later than the first moment and the time step is separated from the first moment.

[0073] S3. If the iteration termination condition is not detected, the second moment and the first moment are updated.

[0074] If the iteration termination condition is not detected, the second moment and the first moment may be updated, wherein the updated first moment is the second moment before the update, and the interval between the updated second moment and the second moment before the update is the time step.

[0075] Step 102: If an iteration termination condition is detected, the simulation parameters at each first moment are used as simulation results.

[0076] The simulation parameters may at least include multiple physical fields.

[0077] In summary, the embodiments of the present application provide a simulation method for laser processing of nanoparticles, in which a computer device can obtain the photoelectric field in the simulation model at the first moment based on the level set physical field in the simulation model at the first moment, and obtain the multi-physical field in the simulation model at the second moment based on the photoelectric field in the simulation model at the first moment during the process of repeatedly executing an iterative process based on a simulation model. If the iteration termination condition is not detected, the second moment and the first moment are updated. If the iteration termination condition is detected, the simulation parameters at each first moment can be used as the simulation result, thereby obtaining the thermal field (i.e., temperature distribution), fluid field, and level set physical field (i.e., the morphology of the nanoparticles) at each first moment in the process of laser processing of nanoparticles. In this way, while achieving high time resolution monitoring of the interaction mechanism between nanoparticles and lasers, there is no need to obtain the interaction mechanism between nanoparticles and lasers through experiments. Compared with related technologies, this method saves time and effort and is more efficient.

[0078] Moreover, since the photoelectric field is affected by the morphology of the nanoparticles, the multi-physics field in the simulation model at the second moment obtained based on the photoelectric field in the simulation model at the first moment can take into account the changes in the photoelectric field caused by the morphological changes of the nanoparticles under laser irradiation, making the calculation results more in line with the actual situation.

[0079] Furthermore, if the iteration termination condition is not detected, the second moment and the first moment are updated. Based on the level set physics field within the updated simulation model at the first moment, the optical and electrical fields within the updated simulation model at the first moment are obtained. That is, the transient results of the updated first moment are used to feed back the calculation of the optical and electrical fields, triggering a new round of optical and electrical field calculations. Subsequently, based on the optical and electrical fields within the updated simulation model at the first moment, the multi-physics fields within the updated simulation model at the second moment are obtained, and multiple iterations are performed until the iteration termination condition is detected. Thus, through a cyclic calculation method, the dynamic trajectory of the optical and electrical fields as they evolve with the nanoparticle morphology is fully captured, ensuring a high degree of consistency between the simulation results and the actual physical process.

[0080] In some embodiments, before step 101, a computer device may construct a simulation model for laser processing of nanoparticles. For example, the nanoparticles may be liquid metal nanoparticles, gold nanoparticles, or silver nanoparticles.

[0081] Figure 2 Schematic diagram of a laser processing nanoparticle provided in an embodiment of the present application. Figure 2 As shown, nanoparticles 10 are located on the side of transparent substrate 20 away from laser light 30. Laser light 30 is incident on the side of transparent substrate 20 away from nanoparticles 10 through objective lens 40 and is focused at the interface between transparent substrate 20 and nanoparticles 10. The diameter of nanoparticles 10 can be 150 nanometers (nm), transparent substrate 20 can be a transparent sapphire substrate, and the pulse width of laser light 30 is in the nanosecond order.

[0082] In an embodiment of the present application, a computer device may construct a simulation model in simulation software. The process of constructing a simulation model of laser processing nanoparticles by a computer device may include the following steps:

[0083] Step 1031: Construct a geometric model.

[0084] According to the actual situation, the geometric model constructed by the computer equipment can be a two-dimensional structural model to improve the calculation efficiency and convergence. Figure 3 The geometric model may be a rectangle, the length d1 of the geometric model may be 10 micrometers (μm), and the width d2 of the geometric model may be 8 μm.

[0085] The geometric model can include a physical domain and a perfectly matched layer domain 50, wherein the perfectly matched layer domain 50 encloses the physical domain. The physical domain can include the region where the transparent substrate 20 is located and a mesh refinement layer 60, wherein the mesh refinement layer 60 encloses the nanoparticles 10, and the region between the mesh refinement layer 60 and the perfectly matched layer domain 50 is air. The thickness of the perfectly matched layer domain 50 is greater than 1 / 2 of the wavelength of the laser 30.

[0086] Since the space around nanoparticles involves multi-field coupling and complex phase changes and fluid motion, computer equipment can mesh the geometric model. Figure 4 is a schematic diagram obtained by meshing the geometric model. Optionally, the mesh can be of any shape, for example, a triangular mesh. Furthermore, the size of the mesh in the mesh refinement layer 60 is smaller than the size of the mesh in the boundary region within the physical domain, and the size of the mesh in the boundary region is smaller than the size of the mesh in the perfectly matched layer domain 50. The boundary region refers to the region within the physical domain excluding the mesh refinement layer 60. Smaller meshes are used within the mesh refinement layer 60, while coarser meshes are used within the boundary region and the perfectly matched layer domain to ensure a balance between computational accuracy and efficiency.

[0087] Step 1032: Construct a photoelectric field calculation model.

[0088] After constructing the geometric model, the computer device can construct an optical field calculation model that can characterize the optical field distribution. The optical field calculation model can satisfy the following requirements:

[0089] Formula (1)

[0090] In formula (1), represents the gradient, is the relative magnetic permeability, E is the optical electric field, is the wave number of the laser, is the relative dielectric constant of the nanoparticles, is the induced current density, is the conductivity, is the dielectric constant of vacuum, is the angular frequency.

[0091] In an embodiment of the present application, the relative magnetic permeability, the wave number of the laser, the induced current density, the electrical conductivity, the vacuum dielectric constant, and the angular frequency are all constants, and the relative magnetic permeability, the wave number of the laser, the induced current density, the electrical conductivity, the vacuum dielectric constant, and the angular frequency are pre-stored in the computer device.

[0092] The computer device can determine the relative permittivity based on the level set field of the nanoparticles. If the level set field is less than a preset value, the relative permittivity is a first relative permittivity. If the level set field is greater than or equal to the preset value, the relative permittivity is a second relative permittivity.

[0093] The first relative dielectric constant is different from the second relative dielectric constant. The computer device can store preset values ​​in advance. , the level set physics in the liquid region and the solid region Therefore, it can be assumed that when the level set field is less than 0.5, the nanoparticles are gaseous, and when the level set field is greater than or equal to 0.5, the nanoparticles are liquid or solid. Therefore, the preset value can be 0.5.

[0094] Optionally, the first relative dielectric constant may be the relative dielectric constant when the nanoparticles are gas, and the second relative dielectric constant may be the relative dielectric constant when the nanoparticles are non-gas. For example, the second relative dielectric constant may be the relative dielectric constant when the nanoparticles are liquid.

[0095] Taking the preset value of 0.5 as an example, the relative dielectric constant Can satisfy:

[0096] Formula (2)

[0097] In formula (2), is the relative dielectric constant when the nanoparticles are gas, is the relative dielectric constant of the nanoparticles when they are liquid, is the level set physics of the nanoparticles.

[0098] Step 1033: Construct a multi-physics field calculation model.

[0099] After building the optical field calculation model, the computer device can build a multi-physics field calculation model. The multi-physics field calculation model can include: a thermal field calculation model, a fluid field calculation model, and a level set physical field calculation model. The thermal field calculation model can meet the following requirements:

[0100] Formula (3)

[0101] is the density, is the heat capacity, is the velocity vector of the fluid, i.e. the fluid field, is the temperature, that is, the thermal field, is the thermal conductivity, is the total heat source, and t is the time.

[0102] The total heat source Can satisfy: Formula (4)

[0103] As heat source for light energy conversion, The heat loss caused by the gasification of nanoparticles. is a constant, and the heat source of the light energy conversion is pre-stored in the computer device .

[0104] Formula (5)

[0105] is the target value, is the imaginary part of the relative dielectric constant of the nanoparticles, It means modulo. It is a normalized Gaussian function that changes with time, which is used to simulate the change of the intensity of the laser light source with time. Computer equipment can obtain The numerical value of .

[0106] Formula (6)

[0107] Formula (7)

[0108] is the mass loss rate of nanoparticles during gasification, is the latent heat of vaporization. is a constant, and the latent heat of vaporization can be pre-stored in the computer device , For the interface function.

[0109] Formula (8)

[0110] is the condensation coefficient (i.e. the coefficient of vapor molecules returning to the liquid region and recombining with liquid molecules), is the atomic mass of the nanoparticle, is the Boltzmann constant, is the evaporation temperature, is standard atmospheric pressure.

[0111] Condensation coefficient , the atomic mass of nanoparticles , Boltzmann constant , evaporation temperature and standard atmospheric pressure All are constants. The condensation coefficients can be pre-stored in the computer equipment. , the atomic mass of nanoparticles , Boltzmann constant , evaporation temperature and standard atmospheric pressure .

[0112] Among them, the interface function The function is to limit the vaporization to the gas-liquid boundary. Can satisfy:

[0113] Formula (9)

[0114] It means modulo.

[0115] Based on the mass conservation equation and taking into account the mass loss caused by gasification, a fluid field calculation model is set up. This fluid field calculation model can meet the following requirements:

[0116] Formula (10)

[0117] represents the vapor density of nanoparticles, Represents the liquid density of the nanoparticles. The vapor density and liquid density of the nanoparticles are both constants, and the liquid density of the nanoparticles can be pre-stored in the computer device.

[0118] The fluid field calculation model can also be set based on the momentum conservation equation. The fluid field calculation model can satisfy:

[0119] Formula (11)

[0120] is the density, is the pressure, is the identity matrix, is the dynamic viscosity, is the melting temperature, is the thermal expansion coefficient, is the gravitational acceleration vector, is the surface tension, is the recoil pressure of steam that the nanoparticles are subjected to when they are gasified. The superscript T in is the transposition symbol. Characterization pair Perform transposition.

[0121] pressure , the identity matrix , melting temperature , thermal expansion coefficient and the gravitational acceleration vector Can be constants, and pressure can be pre-stored in the computer device , the identity matrix , melting temperature , thermal expansion coefficient and the gravitational acceleration vector .

[0122] Formula (12)

[0123] represents the surface tension coefficient of the nanoparticles, is the surface curvature, is the surface unit vector.

[0124] Surface tension coefficient , surface curvature and the surface unit vector They are all constants. The surface tension coefficient can be pre-stored in the computer device. , surface curvature and the surface unit vector .

[0125] Formula (13)

[0126] The level set physics calculation model can meet the following requirements:

[0127] Formula (14)

[0128] In the above formula, Representing Level Set Physics The partial derivative with respect to time t. The level set physics field at the gas-liquid interface is 0.5, and the level set physics field Between 0 and 1. is the preset boundary layer thickness, As the initial value, the computer device can pre-store the preset boundary layer thickness and the initial value. Set to 1 / 15 of the maximum value of the grid division.

[0129] In the embodiment of the present application, a simulation model can be set in the simulation software, and the target physical parameters can be generated by the simulation software. The target physical parameters may include thermal conductivity ,density , heat capacity , dynamic viscosity It should be noted that, for each target physical parameter, the target physical parameter at different moments may be different, and the target physical parameter of different grids may also be different.

[0130] In an embodiment of the present application, in the process of calculating multiple physical fields, the computer device can use the above-mentioned formula 3, formula 10, formula 11 and formula 14 to simultaneously determine the thermal field, fluid field and level set physical field.

[0131] Step 1034: Construct a cyclic calculation process of the optical and electrical fields and the multi-physical fields.

[0132] After constructing the multi-physics field, the computer device can construct a cyclic calculation process of the optical field and the multi-physics field. The cyclic calculation process may include repeatedly executing the iterative process until the iterative termination condition is detected. Figure 5 The iterative process may include the following steps A1 to A4:

[0133] A1. Based on the level set physical field in the simulation model at the first moment, obtain the optical and electrical field in the simulation model at the first moment.

[0134] The computer device can obtain the optical and electrical field in the simulation model at the first moment based on the level set physical field in the simulation model at the first moment.

[0135] In an embodiment of the present application, the computer device can obtain the relative dielectric constant of the nanoparticle at the first moment based on the level set physical field at the first moment, and then obtain the optical field in the simulation model at the first moment based on the relative dielectric constant at the first moment and the optical field calculation model.

[0136] Optionally, the computer device may input the optical field calculation parameters and the relative dielectric constant at the first moment into the optical field calculation model to obtain the optical field within the simulation model at the first moment. The optical field calculation parameters may include parameters in the optical field calculation model other than the optical field and the relative dielectric constant.

[0137] In the embodiment of the present application, if the level set field at the first moment is less than a preset value, the relative permittivity of the nanoparticle at the first moment is the first relative permittivity. If the level set field at the first moment is greater than or equal to the preset value, the relative permittivity of the nanoparticle at the first moment is the second relative permittivity.

[0138] The first relative dielectric constant is different from the second relative dielectric constant. The first relative dielectric constant is the relative dielectric constant when the nanoparticles are gas, and the second relative dielectric constant is the relative dielectric constant when the nanoparticles are non-gas.

[0139] Since the relative dielectric constant of nanoparticles is related to the level set physical field, it can reflect the influence of the morphology of nanoparticles on the photoelectric field.

[0140] When the iterative process is first executed, the multiphysics fields within the simulation model at the first moment are determined based on the initial photoelectric fields.

[0141] In some embodiments, the initial optical electric field may be pre-stored in the computer device, and the initial optical electric field is determined based on the initial optical electric field calculation parameters.

[0142] In some embodiments, the computer device may pre-store initial optical field calculation parameters, and the computer device may input the initial optical field calculation parameters into the optical field calculation model to obtain the initial optical field.

[0143] The initial optical field calculation parameters may include parameters other than the optical field in the optical field calculation model (such as the above formula 1 and formula 2).

[0144] In some embodiments, the initial relative dielectric constant in the initial optical electric field calculation parameters may be pre-stored in the computer device.

[0145] In some embodiments, the computer device may determine the initial relative permittivity based on a relationship between a pre-stored initial level set physical field and a preset value. The computer device may pre-store the initial level set physical field.

[0146] After determining the initial photoelectric field, the computer device can input the initial photoelectric field, the initial level set physical field, and the initial multi-physical field calculation parameters into the multi-physical field calculation model to obtain the multi-physical field in the simulation model at the first moment when the iterative process is executed for the first time.

[0147] The initial multi-physics field calculation parameters may include the parameters in Formulas 3 to 14 except for the photoelectric field, thermal field, fluid field, the level set field in Formula 6, and the level set field in Formulas 7, 9 to 14. The level set field in Formula 6 is the initial level set field.

[0148] When this is not the first iteration, the multi-physics field in the simulation model at the first moment is determined by the previous iteration.

[0149] A2. Set the time step.

[0150] If the morphology of the nanoparticles changes dramatically at the first moment, the time step can be set to the first time step. If the morphology of the nanoparticles changes moderately at the first moment, the time step can be set to the second time step. The first time step is smaller than the second time step.

[0151] The computer device can obtain multiple change speeds of the boundary of the nanoparticle at the first moment. The change speed refers to the speed at which the boundary position of the nanoparticle changes over time. If the maximum absolute value of the multiple change speeds is Greater than or equal to the speed threshold , it can be determined that the morphology of the nanoparticles changes dramatically. If the maximum value of the absolute value of multiple change rates Less than the speed threshold , it can be determined that the morphology of the nanoparticles changes moderately.

[0152] That is, in In the case of ,exist In the case of .Should is the first time step, The computer device may pre-store a speed threshold, for example, the speed threshold may be 100 meters per second (m / s).

[0153] Computer equipment can obtain multiple changing speeds of nanoparticle boundaries through simulation software.

[0154] It should be noted that setting the time step ensures the controllability and accuracy of the calculation process. During laser processing of nanoparticles, the severity of the nanoparticle morphological changes is not constant; some periods of time experience mild changes, while others experience more dramatic changes. When the nanoparticle morphology changes dramatically, a shorter first time step is required to achieve more accurate calculation results. Conversely, when the nanoparticle morphology changes more moderately, a longer second time step is required. This achieves a balance between calculation accuracy and efficiency.

[0155] And, the time step The size of determines the degree of fit between the final calculation result and the actual situation. The smaller it is, the higher the degree of fit. And the speed threshold The value of needs to be estimated according to the specific situation. The speed threshold The smaller the value, the more accurate the calculation result but the lower the calculation efficiency. The larger it is, the less accurate the calculation result will be but the calculation efficiency will be higher.

[0156] A3. Based on the photoelectric field in the simulation model at the first moment, obtain the multi-physical field in the simulation model at the second moment of the time step after the first moment.

[0157] After obtaining the optical and electrical fields within the simulation model at a first moment, the computer device may obtain the multi-physics fields within the simulation model at a second moment based on the optical and electrical fields within the simulation model at the first moment, wherein the second moment is later than the first moment and the second moment is separated from the first moment by a time step.

[0158] In an embodiment of the present application, the computer device can obtain the multi-physical field in the simulation model at a second moment that is a time step after the first moment based on the optical and electrical field in the simulation model at the first moment.

[0159] The computer device can input the multi-physics field calculation parameters, the photoelectric field in the simulation model at the first moment, and the level set physical field at the first moment into the multi-physics field calculation model to obtain the multi-physics field in the simulation model at the second moment.

[0160] Among them, the multi-physics field calculation parameters can include the parameters in Formulas 3 to 14 except the photoelectric field, thermal field, fluid field, the level set physics field in Formula 6, and the level set physics field in Formulas 7, 9 to 14, and the level set physics field in Formula 6 is the level set physics field at the first moment.

[0161] A4. If no iteration termination condition is detected, the first moment and the second moment are updated.

[0162] If the computer device does not detect the iteration termination condition, it may update the first moment and the second moment and execute step A1 again. The updated first moment is the second moment, and the interval between the updated second moment and the second moment before the update is the time step. For example, the updated first moment is the second moment.

[0163] Furthermore, the computer device may store the optical and electrical fields and the multi-physical fields at the first moment, thereby avoiding being overwritten by the data (such as the optical and electrical fields and the multi-physical fields) at the first moment of the next iteration.

[0164] In some embodiments, the simulation model is divided into multiple grids. After obtaining the multi-physics field within the simulation model at a second moment based on the photoelectric field within the simulation model at a first moment, the computer device can obtain the level set physics field of the grid, thereby obtaining the level set physics fields of multiple grids. If the maximum value of the level set physics fields of the multiple grids is greater than or equal to a level set physics field threshold, it can be determined that the nanoparticles are not completely vaporized, and therefore, it can be determined that the iteration termination condition has not been detected. The level set physics field threshold can be pre-stored in the computer device.

[0165] In some embodiments, if the iteration duration of the iterative process does not reach the termination duration, the computer device may determine that the iteration termination condition has not been detected. The iteration duration may be the interval between the start time of the first execution of the iterative process and the detection time, where the detection time is the time when the iteration termination condition is detected. The computer device may pre-store the termination duration.

[0166] In some embodiments, the computer device may determine that the iteration termination condition has not been detected when detecting that the number of iterations has not reached the maximum number of iterations. The maximum number of iterations may be pre-stored in the computer device.

[0167] When an iteration termination condition is detected, the computer device may stop the loop calculation.

[0168] Step 1035: Set the material physical parameters.

[0169] Among them, the material physical parameters may at least include: optical parameters of the laser, physical parameters required by the optical field calculation model and the multi-physics field calculation model, and the physical parameters may include: initial optical field calculation parameters, initial level set physical field, constants in the optical field calculation model and the multi-physics field calculation model.

[0170] The optical parameters may include laser spot size, focal plane position, wave number, etc. Optionally, a paraxial approximation may be selected to simulate Gaussian light speed.

[0171] In some embodiments, the specific implementation process of step 102 may be the iterative process in the above-mentioned step 101, which will not be described in detail in the embodiment of the present application.

[0172] In some embodiments, if an iteration termination condition is detected, the computer device may use the simulation parameters at each first moment as the simulation result, and the simulation parameters may include at least multiple physical fields. Optionally, the simulation parameters may also include the recoil pressure of the steam when the nanoparticles are vaporized. .

[0173] In some embodiments, if the maximum value of the plurality of level set physics fields is less than the level set physics field threshold, it can be determined that the nanoparticles have been completely vaporized, and thus it can be determined that the iteration termination condition has been detected.

[0174] In some embodiments, when the iteration duration of the iterative process reaches the termination duration, the computer device may determine that an iteration termination condition is detected.

[0175] In some embodiments, the computer device determines that an iteration termination condition is detected when detecting that the number of iterations reaches a maximum number of iterations.

[0176] For each grid, the computer device can determine the simulation parameters of each grid using the above method, thereby achieving high spatial resolution monitoring of the processing process.

[0177] The simulation method for laser processing of nanoparticles provided in the embodiment of the present application monitors the processing process with high spatial resolution and high temporal resolution, including temperature distribution, phase change, stress conditions of nanoparticles and changes in their morphology. Based on the simulation results of the present application, in-depth research can be conducted on nanoscale laser processing problems, which is conducive to the understanding of the mechanism of nanoscale laser processing and provides a theoretical basis for the adjustment of experimental parameters. In addition, the changes in light field distribution caused by a series of morphological changes of nanoparticles under laser irradiation are taken into account, so that the calculation results are more in line with the actual situation. Under the premise of maintaining high precision, this simulation method can perform a full-scale, high-fidelity simulation and reproduction of the complex process of laser processing of nanoparticles, providing strong support for in-depth exploration of its inherent physical mechanism, while pointing out the direction for the optimization selection of experimental parameters and inspiring more innovative application inspiration.

[0178] In summary, the embodiments of the present application provide a method for laser processing nanoparticles, in which a computer device can obtain the photoelectric field in the simulation model at the first moment based on the level set physical field in the simulation model at the first moment, and obtain the multi-physical field in the simulation model at the second moment based on the photoelectric field in the simulation model at the first moment during the process of repeatedly executing an iterative process based on a simulation model. If the iteration termination condition is not detected, the second moment and the first moment are updated. If the iteration termination condition is detected, the simulation parameters at each first moment can be used as the simulation result, thereby obtaining the thermal field (i.e., temperature distribution), fluid field, and level set physical field (i.e., the morphology of the nanoparticles) at each first moment during the laser processing of nanoparticles. Since high-time-resolution monitoring of the interaction mechanism between nanoparticles and laser light is achieved without the need to obtain the interaction mechanism between nanoparticles and laser light through experiments, compared with related technologies, this method saves time and effort and is more efficient.

[0179] In some embodiments, the computer device may establish a simulation model according to step 301. Figure 3 The size of the nanoparticles in the image is 150 nm. The size of the geometric model can be 10 μm × 8 μm, the mesh refinement layer can be rectangular, and the size of the mesh refinement layer can be 1 μm × 0.5 μm. The thickness of the perfectly matched layer domain can be 2 μm.

[0180] The meshes in the geometric model are all triangular meshes. The mesh size in the perfect matching layer domain is 0.75nm-200nm, the mesh size in the mesh refinement layer is 0.08nm-20nm, and the mesh size in the remaining areas is 0.16nm-50nm.

[0181] The end time of the loop calculation process is 5ns, and the first time step is , the second time step .

[0182] In this embodiment, the calculation start time is set to the time when the incident laser starts irradiating, that is, the first first moment. The incident laser is a nanosecond laser with a pulse width of 5ns, a wavelength of 1064nm, a spot radius of 17μm, and an energy density of 20 joules per square centimeter (J / cm 2 ).

[0183] After the calculation based on the simulation model is completed, the computer equipment can visualize the simulation parameters and obtain the nanoparticles with a diameter of 150nm at 20J / cm 2 The morphology, temperature distribution and recoil pressure change with time under nanosecond laser irradiation. Figures 6 to 11 Schematic diagram of the simulation parameters of nanoparticles.

[0184] The coordinate system in this diagram is established with the target point of the nanoparticle in the geometric model as its origin. This target point is in contact with the mesh refinement layer 60. The coordinate system includes a horizontal axis and a vertical axis, both in μm. The horizontal axis is parallel to the width of the geometric model, and the vertical axis is parallel to the length of the geometric model.

[0185] in, Figure 6 is a schematic diagram of the volume fraction of nanoparticles at 0.5ns. Figure 7 Schematic diagram of the temperature distribution of nanoparticles at 0.5ns. Figure 8 Schematic diagram of the recoil pressure on the nanoparticles at 0.5ns.

[0186] Figure 9 is a schematic diagram of the volume fraction of nanoparticles at 5ns. Figure 10 is a schematic diagram of the temperature distribution of nanoparticles at 1ns. Figure 11Schematic diagram of the recoil pressure on the nanoparticles at 5ns.

[0187] from Figures 6 to 11 The temperature distribution and morphology of the nanoparticles at different times, as well as the changes in recoil pressure, can be seen. Under the action of the laser, the nanoparticles rapidly heat up, reaching their vaporization temperature. Near the transparent substrate, they undergo a dramatic phase transition (from liquid to gas), forming cavitation bubbles. Furthermore, the nanoparticles deform under the influence of the vaporization recoil pressure.

[0188] In other embodiments, the computer device may establish a simulation model according to step 301. Figure 3 The size of the nanoparticles in the model is 100 nm, the size of the geometric model is 10 μm × 8 μm, the size of the mesh refinement layer is 1 μm × 0.5 μm, and the thickness of the perfectly matched layer domain can be 2 μm.

[0189] All meshes in the geometric model are triangular meshes. The mesh size in the perfect matching layer domain is 0.75nm-200nm, the mesh size in the mesh refinement layer is 0.08nm-20nm, and the mesh size in the remaining areas is 0.16nm-50nm.

[0190] The end time of the loop calculation process is set to 5ns, and the first time step is , the second time step .

[0191] In this embodiment, the calculation start time is set to the time when the incident laser starts irradiating, that is, the first first moment. The incident laser is a nanosecond laser, the laser pulse width is 5ns, the laser wavelength is 1064nm, the laser spot radius is 17μm, and the laser energy density is 5J / cm 2 .

[0192] After the calculation based on the simulation model is completed, the computer equipment can visualize the simulation parameters and obtain the nanoparticles with a diameter of 100nm at 5J / cm 2 Changes in morphology, temperature distribution, and recoil pressure over time under nanosecond laser irradiation.

[0193] Figures 12 to 17 Schematic diagram of simulation parameters for nanoparticles in a geometric model. The coordinate system in this diagram is established with the target point of the nanoparticle in the geometric model as the origin, and the target point is in contact with the mesh refinement layer 60. The coordinate system includes a horizontal axis and a vertical axis, both in μm.

[0194] in, Figure 12 is a schematic diagram of the volume fraction of nanoparticles at 0.5ns. Figure 13 is a schematic diagram of the temperature distribution of nanoparticles at 0.5ns. Figure 14 Schematic diagram of the recoil pressure on the nanoparticles at 0.5ns.

[0195] Figure 15 is a schematic diagram of the volume fraction of nanoparticles at 5ns. Figure 16 is a schematic diagram of the temperature distribution of nanoparticles at 5ns. Figure 17 Schematic diagram of the recoil pressure exerted on the nanoparticles at 5ns.

[0196] from Figures 12 to 17 It can be seen that the temperature distribution, morphology changes of the nanoparticles at different times, as well as the changes in the recoil pressure they are subjected to, are significant morphological changes that occur when the recoil pressure generated by the vaporization acts on the surface of the nanoparticles.

[0197] Figures 6 to 17 The simulation effect of laser processing of nanoparticles in the embodiment of the present application is demonstrated, and its high spatial resolution and high temporal resolution are verified.

[0198] An embodiment of the present application provides a computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the simulation method for laser processing nanoparticles described in the above embodiment is implemented.

[0199] Figure 18 This is a schematic diagram of the structure of a computer device provided in an embodiment of the present application. Figure 18 As shown, the computer device includes a memory 1801, a processor 1802, and a computer program stored in the memory 1801 and executable on the processor 1802. When the processor 1802 executes the computer program, the simulation method for laser processing nanoparticles described in the above embodiment is implemented.

[0200] Figure 19 This is a block diagram of a simulation device for laser processing nanoparticles provided in an embodiment of the present application, such as Figure 19 As shown, the device includes:

[0201] Construction module 1901, for constructing a simulation model of laser processing nanoparticles;

[0202] The iterative process execution module 1902 is configured to repeatedly execute the iterative process based on the simulation model during the process of simulating laser processing of nanoparticles based on the simulation model until an iteration termination condition is detected. The iterative process includes:

[0203] Based on the level set physical field in the simulation model at the first moment, the photoelectric field in the simulation model at the first moment is obtained, and based on the photoelectric field in the simulation model at the first moment, the multi-physical field in the simulation model at the second moment is obtained; wherein the multi-physical field includes at least a thermal field, a fluid field, and a level set physical field, the second moment is later than the first moment, and the second moment and the first moment are separated by a time step;

[0204] If the iteration termination condition is not detected, the first moment and the second moment are updated; wherein the updated first moment is the second moment before the update, and the interval between the updated second moment and the second moment before the update is the time step;

[0205] The determination module 1903 is configured to use the simulation parameters at each first moment as the simulation result if an iteration termination condition is detected, where the simulation parameters include at least multiple physical fields.

[0206] Optionally, if the morphology of the nanoparticles changes dramatically at the first moment, the time step is the first time step;

[0207] If the morphological change of the nanoparticles at the first moment is mild, the time step is the second time step;

[0208] The first time step is smaller than the second time step.

[0209] Optionally, the iterative process execution module 1902 is further configured to:

[0210] Acquire multiple changing velocities of the boundary of the nanoparticle at a first moment;

[0211] If the maximum value of the absolute values ​​of the multiple change speeds is greater than or equal to the speed threshold, it is determined that the morphology of the nanoparticles changes dramatically;

[0212] If the maximum value of the absolute values ​​of the multiple change speeds is less than the speed threshold, it is determined that the morphology change of the nanoparticles is moderate.

[0213] Optionally, the simulation model includes multiple grids; the iterative process execution module 1902 is further configured to:

[0214] After obtaining the multi-physics field in the simulation model at the second moment based on the photoelectric field in the simulation model at the first moment, if the maximum value of the level set physics field of multiple grids is less than the level set physics field threshold, it is determined that the iteration termination condition is detected.

[0215] Optionally, the iterative process execution module 1902 is configured to:

[0216] Obtaining the relative dielectric constant of the nanoparticles at the first moment based on the level set physical field in the simulation model at the first moment;

[0217] Based on the relative dielectric constant at the first moment and the optical field calculation model, the optical field in the simulation model at the first moment is obtained.

[0218] The iterative process execution module 1902 is used to:

[0219] If the level set physical field is less than a preset value, the relative dielectric constant of the nanoparticle is a first relative dielectric constant;

[0220] If the level set physical field is greater than or equal to the preset value, the relative permittivity is the second relative permittivity;

[0221] The first relative permittivity is different from the second relative permittivity.

[0222] Optionally, the first relative dielectric constant is the relative dielectric constant when the nanoparticles are gas, and the second relative dielectric constant is the relative dielectric constant when the nanoparticles are non-gas.

[0223] In summary, an embodiment of the present application provides a device for laser processing nanoparticles. In the process of repeatedly executing an iterative process based on a simulation model, the device can obtain the photoelectric field in the simulation model at the first moment based on the level set physical field in the simulation model at the first moment, and obtain the multi-physical field in the simulation model at the second moment based on the photoelectric field in the simulation model at the first moment. If the iteration termination condition is not detected, the second moment and the first moment are updated. If the iteration termination condition is detected, the simulation parameters of each first moment can be used as the simulation result, thereby obtaining the thermal field (i.e., temperature distribution), fluid field, and level set physical field (i.e., the morphology of the nanoparticles) at each first moment in the process of laser processing nanoparticles. Since high-time-resolution monitoring of the interaction mechanism between nanoparticles and lasers is achieved, there is no need to obtain the interaction mechanism between nanoparticles and lasers through experiments. Compared with related technologies, this method saves time and effort and is more efficient.

[0224] It should be noted that the logic and / or steps represented in the flowcharts or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing the logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (e.g., a computer-based system, a system including a processor, or other system that can fetch and execute instructions from an instruction execution system, apparatus, or device). For purposes of this specification, a "computer-readable medium" can be any device that can contain, store, communicate, propagate, or transport a program for use by, or in conjunction with, an instruction execution system, apparatus, or device. More specific examples (non-exhaustive list) of computer-readable media include the following: an electrical connection with one or more wires (electronic device), a portable computer disk cartridge (magnetic device), random access memory (RAM), read-only memory (ROM), erasable and programmable read-only memory (EPROM or flash memory), fiber optic devices, and a portable compact disc read-only memory (CDROM). Furthermore, the computer-readable medium may even be paper or other suitable medium on which the program is printed, since the program may be obtained electronically, for example, by optically scanning the paper or other medium and then editing, interpreting or processing it in another suitable manner if necessary, and then storing it in a computer memory.

[0225] It should be understood that various components of the present invention may be implemented using hardware, software, firmware, or a combination thereof. In the above-described embodiments, multiple steps or methods may be implemented using software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented using hardware, as in another embodiment, any one of the following technologies known in the art or a combination thereof may be used: a discrete logic circuit having logic gate circuits for implementing logic functions on data signals, an application-specific integrated circuit having suitable combinational logic gate circuits, a programmable gate array (PGA), a field-programmable gate array (FPGA), etc.

[0226] Throughout this specification, reference to terms such as "one embodiment," "some embodiments," "examples," "specific examples," or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with that embodiment or example are included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0227] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like to indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0228] In addition, the terms "first" and "second" used in the embodiments of the present invention are only used for descriptive purposes and should not be understood as indicating or implying relative importance, or implicitly indicating the number of technical features indicated in this embodiment. Therefore, the features defined by the terms "first" and "second" in the embodiments of the present invention can explicitly or implicitly indicate that the embodiment includes at least one of such features. In the description of the present invention, the word "plurality" means at least two or two or more, such as two, three, four, etc., unless otherwise clearly and specifically defined in the embodiments.

[0229] In the present invention, unless otherwise clearly specified or limited in the embodiments, the terms "installed," "connected," "connect," and "fixed" appearing in the embodiments should be understood in a broad sense. For example, the connection may be a fixed connection, a detachable connection, or an integral connection. It can also be a mechanical connection, an electrical connection, etc.; of course, it can also be a direct connection, or an indirect connection through an intermediate medium, or it can be internal communication between two elements, or an interaction between two elements. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood based on the specific implementation.

[0230] In the present invention, unless otherwise expressly specified or limited, when a first feature is "above" or "below" a second feature, it may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediary. Furthermore, when a first feature is "above," "above," or "above" a second feature, it may mean that the first feature is directly above or diagonally above the second feature, or simply means that the first feature is at a higher level than the second feature. When a first feature is "below," "below," or "below" a second feature, it may mean that the first feature is directly below or diagonally below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0231] Although the embodiments of the present invention have been shown and described above, it will be understood that the above embodiments are illustrative and are not to be construed as limitations on the present invention. A person skilled in the art may change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A simulation method for laser processing of nanoparticles, characterized in that: The method comprises: In a process of simulating laser processing of nanoparticles based on a simulation model, an iterative process is repeatedly performed based on the simulation model until an iteration termination condition is detected; the iterative process includes: Based on the level set physical field in the simulation model at the first moment, the relative dielectric constant of the nanoparticles at the first moment is obtained, based on the relative dielectric constant and the optical field calculation model at the first moment, the optical field in the simulation model at the first moment is obtained, and the multi-physics field calculation parameters, the optical field in the simulation model at the first moment, and the level set physical field at the first moment are input into the multi-physics field calculation model to obtain the multi-physics field in the simulation model at the second moment; the multi-physics field includes at least a thermal field, a fluid field, and the level set physical field, the second moment is later than the first moment, and the second moment is separated from the first moment by a time step; If the iteration termination condition is not detected, updating the first moment and the second moment; the updated first moment is the second moment before the update, and the second moment after the update is separated from the second moment before the update by the time step; If the iteration termination condition is detected, the simulation parameters at each of the first moments are used as simulation results, and the simulation parameters at least include the multi-physical field.

2. The simulation method for laser processing nanoparticles according to claim 1, characterized in that: If the morphology of the nanoparticles changes dramatically at the first moment, the time step is the first time step; If the morphology of the nanoparticles changes gently at the first moment, the time step is the second time step; The first time step is smaller than the second time step.

3. The simulation method for laser processing nanoparticles according to claim 2, characterized in that: The method further comprises: Acquire multiple changing speeds of the boundary of the nanoparticle at the first moment; If the maximum value of the absolute values ​​of the multiple change speeds is greater than or equal to the speed threshold, it is determined that the morphology of the nanoparticle changes dramatically; If the maximum value of the absolute values ​​of the multiple change speeds is less than the speed threshold, it is determined that the morphology change of the nanoparticles is moderate.

4. The simulation method for laser processing nanoparticles according to any one of claims 1 to 3, characterized in that: The simulation model includes a plurality of grids; after obtaining a multi-physical field within the simulation model at a second moment based on the optical and electrical fields within the simulation model at the first moment, the method further includes: If the maximum value of the level set physics fields of the plurality of grids is less than a level set physics field threshold, it is determined that the iteration termination condition is detected.

5. The simulation method for laser processing nanoparticles according to claim 4, characterized in that: Obtaining the relative dielectric constant of the nanoparticle at the first moment based on the level set physical field in the simulation model at the first moment includes: If the level set physical field is less than a preset value, the relative dielectric constant of the nanoparticle is a first relative dielectric constant; If the level set physical field is greater than or equal to a preset value, the relative dielectric constant is a second relative dielectric constant; The first relative permittivity is different from the second relative permittivity.

6. The simulation method for laser processing nanoparticles according to claim 5, characterized in that: The first relative dielectric constant is the relative dielectric constant when the nanoparticles are gas, and the second relative dielectric constant is the relative dielectric constant when the nanoparticles are non-gas.

7. A computer-readable storage medium, characterized in that A computer program is stored thereon, and when the computer program is executed by a processor, the simulation method for laser processing nanoparticles according to any one of claims 1 to 6 is implemented.

8. A computer device, characterized in that: The method comprises a memory, a processor and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the method for simulating laser processing of nanoparticles according to any one of claims 1 to 6 is implemented.

9. A simulation device for laser processing nanoparticles, characterized in that: The device comprises: The iterative process execution module is used to repeatedly execute the iterative process based on the simulation model during the process of simulating laser processing of nanoparticles based on the simulation model until an iteration termination condition is detected; the iterative process includes: Based on the level set physical field in the simulation model at the first moment, the relative dielectric constant of the nanoparticles at the first moment is obtained, based on the relative dielectric constant and the optical field calculation model at the first moment, the optical field in the simulation model at the first moment is obtained, and the multi-physics field calculation parameters, the optical field in the simulation model at the first moment, and the level set physical field at the first moment are input into the multi-physics field calculation model to obtain the multi-physics field in the simulation model at the second moment; the multi-physics field includes at least a thermal field, a fluid field, and the level set physical field, the second moment is later than the first moment, and the second moment is separated from the first moment by a time step; If the iteration termination condition is not detected, updating the first moment and the second moment; the updated first moment is the second moment before the update, and the second moment after the update is separated from the second moment before the update by the time step; A determination module is configured to use the simulation parameters at each of the first moments as simulation results if the iteration termination condition is detected, wherein the simulation parameters at least include the multi-physical field.

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