Diamond crystal multi-phonon intrinsic absorption band regulating device and transmittance regulating method

Abstract

The application provides a diamond crystal multi-phonon intrinsic absorption band regulation device and a transmittance regulation method.The device comprises a diamond crystal, a multi-phonon absorption band regulation module and a transmittance regulation module.Based on the diamond crystal multi-phonon intrinsic absorption band regulation device, stress is applied to the diamond crystal, the vibration mode of the diamond crystal is regulated, the multi-phonon combination of the diamond crystal is controlled, the range of the multi-phonon absorption band of the diamond crystal is regulated, the absorption of the pump laser is reduced, the transmittance of the pump laser is increased, the stress applied to the diamond crystal is regulated by combining with a real-time transmittance regulation method, and then the transmittance of the pump laser passing through the diamond crystal meets the use requirement.The range of the multi-phonon intrinsic absorption band of the diamond crystal can be regulated, the absorption of the pump laser wavelength is reduced, the 'barrier' generated by the intrinsic absorption band is broken, and a new wavelength of high-beam-quality and high-power diamond Raman laser is output.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of laser, in particular to a diamond crystal multi-phonon intrinsic absorption band regulation device and a transmittance regulation method. BACKGROUND

[0002] Diamond crystal has excellent optical properties such as high Raman gain, large Raman shift and wide transmittance range, and has high thermal conductivity and high hardness. With the maturity of its growth technology, diamond crystal has become an important Raman gain medium for obtaining high-power, high-beam-quality and new-wavelength lasers. Diamond Raman laser has great development prospects in the fields of industrial laser processing, eye-safe laser and multi-wavelength laser. Diamond Raman lasers in the range of ultraviolet 275 nm to mid-infrared 3.8 μm have been obtained.

[0003] However, due to the multi-phonon intrinsic absorption band of diamond crystal in the range of 3.75-6.5 μm, it is difficult to obtain diamond Raman laser output within the intrinsic absorption band. It also limits the output of diamond Raman laser wavelength whose pump laser wavelength is within the intrinsic absorption band. In order to break through the "barrier" caused by the intrinsic absorption band, a solution is needed to regulate the range of the intrinsic absorption band of diamond crystal, which provides a feasible technology for expanding new wavelengths and improving conversion efficiency of diamond Raman laser. SUMMARY

[0004] The present application provides a diamond crystal multi-phonon intrinsic absorption band regulation device and a real-time transmittance regulation method, which provides a new and feasible technical solution for regulating the range of the multi-phonon intrinsic absorption band of diamond crystal. The range of the multi-phonon intrinsic absorption band can be regulated by the diamond crystal multi-phonon intrinsic absorption band regulation device and the real-time transmittance regulation method, the transmittance of the pump laser wavelength is increased and the absorption is reduced. The "barrier" of the intrinsic absorption band is broken, which provides a feasible technical solution and device for outputting new-wavelength laser and improving conversion efficiency of diamond Raman laser.

[0005] The first aspect of the present application provides a diamond crystal multi-phonon intrinsic absorption band regulation device, comprising:

[0006] The diamond crystal includes two oppositely parallel stress application surfaces and two oppositely arranged light transmission end surfaces;

[0007] The multi-phonon absorption band regulating module is used for regulating the multi-phonon combination mode by regulating the vibration mode of the diamond crystal, so as to control the range of the multi-phonon intrinsic absorption band of the diamond crystal. The multi-phonon absorption band regulating module comprises a multifunctional stressor and a diamond anvil cell which are communicatively connected. The diamond anvil cell is arranged on the stress application surface. The multifunctional stressor is arranged on the side of the diamond anvil cell away from the stress application surface. The stress applied by the multifunctional stressor is transmitted to the diamond crystal through the diamond anvil cell to regulate the vibration mode of the diamond crystal.

[0008] The transmittance regulating module is used for regulating the transmittance of the pump laser in the diamond crystal. The transmittance regulating module comprises a wide-tunable laser source, a light splitting monitor, a first detector, a central controller and a second detector which are communicatively connected. The wide-tunable laser source is used for emitting the pump laser. The wavelength of the pump laser can be tuned in a wide range. The light splitting monitor splits the pump laser according to a preset light splitting ratio to generate first light splitting and second light splitting. The first light splitting is converted into a monitoring signal after being received by the first detector and is transmitted to the central controller. The second light splitting is transmitted to the second detector after penetrating the diamond crystal and is converted into a detection signal and transmitted to the central controller. The central controller regulates the stress applied by the multifunctional stressor, the wavelength of the pump laser and the ratio of the first light splitting and the second light splitting according to preset parameters. The central controller calculates the real-time transmittance of the pump laser according to the monitoring signal, the detection signal and the preset light splitting ratio. The central controller compares the real-time transmittance with a preset transmittance to generate a stress regulating signal. The stress regulating signal is transmitted to the multifunctional stressor to regulate the vibration mode of the diamond crystal and the range of the multi-phonon intrinsic absorption band so as to meet the preset transmittance.

[0009] According to an embodiment of the present application, the range of the multi-phonon intrinsic absorption band is , the stress and are related as , wherein a and b are stress constants, is the Raman shift of the diamond without stress, is the Raman shift of the diamond under stress.

[0010] According to an embodiment of the present application, the values of a and b are in the range of a=517±4GPa and b=764±14GPa.

[0011] According to an embodiment of the present application, the multi-phonon absorption band regulating module comprises a stress shaper arranged between the diamond anvil cell and the diamond crystal, which is used for adjusting the stress size and direction applied to the diamond crystal.

[0012] According to one embodiment of the present application, the multi-phonon absorption band regulation module comprises a stress protector, which is arranged between the diamond anvil and the side of the diamond crystal light transmission surface.

[0013] According to one embodiment of the present application, the transmittance regulation module further comprises a beam shaper, which regulates the beam waist, divergence angle, polarization state, phase, and amplitude of the laser emitted by the wide-tunable laser source.

[0014] According to one embodiment of the present application, the beam splitter monitors the wavefront, amplitude, power, and energy of the pump laser according to a splitting ratio, which can be continuously changed.

[0015] According to one embodiment of the present application, the laser wavelength range of the wide-tunable laser source covers 2 μm ~ 15 μm, and the tuning accuracy is ≤ 10 nm.

[0016] According to one embodiment of the present application, the first detector and the second detector can be a wavefront detector, an energy detector, a power detector, or an interferometer.

[0017] The second aspect embodiment of the present application provides a transmittance regulation method, which is used in the diamond crystal multi-phonon intrinsic absorption band regulation device as described above, and the transmittance regulation method comprises the following steps:

[0018] Parameters of the central controller are set, the parameters include a pump laser wavelength, a preset splitting ratio, a preset transmittance of the pump laser wavelength, and a preset transmittance difference value, and the central controller regulates the output of the pump laser wavelength, the ratio of the first splitting and the second splitting of the wide-tunable laser source according to the set parameters, and outputs a stress signal to the multifunctional stressor;

[0019] The multifunctional stressor receives the stress signal to apply stress, the applied stress is applied to the diamond crystal through the diamond anvil, the vibration mode of the diamond crystal is regulated, and the range of the multi-phonon intrinsic absorption band is further regulated; the wide-tunable laser source emits the pump laser, the pump laser is split by the beam splitter to generate the first splitting and the second splitting, the first splitting is transmitted to the first detector, converted into a monitoring signal, and then transmitted to the central controller, and the second splitting penetrates the diamond crystal, transmitted to the second detector, and converted into the detection signal and then transmitted to the central controller;

[0020] The central controller receives the monitoring signal and the detection signal, calculates the real-time transmittance of the pump laser according to the preset splitting ratio in real time, compares the real-time transmittance with the preset transmittance, and obtains a real-time transmittance difference value.

[0021] The central controller outputs a stress control signal to the multifunctional stressor according to the difference between the real-time transmittance difference value and the preset transmittance difference value, and repeats the second step, the third step and the fourth step until the real-time transmittance difference value is less than or equal to the preset transmittance difference value, and finally obtains the transmittance of the pump laser that meets the demand.

[0022] The application provides a diamond crystal multi-phonon intrinsic absorption band control device and a real-time transmittance control method. The multi-phonon absorption band control module is used to control the vibration mode of the diamond crystal, and then the multi-phonon combination mode in the diamond crystal is controlled, so as to control the range of the multi-phonon intrinsic absorption band of the diamond crystal and reduce the absorption of the pump laser. Based on the transmittance control module, the real-time transmittance control method is used to further control the transmittance of the pump laser wavelength, and the index of the transmittance is monitored in real time, so that the transmittance meets the use demand. The technical scheme breaks the "barrier" of the intrinsic absorption band, solves the problem that the laser wavelength in the intrinsic absorption band range of the diamond crystal cannot be output or used as the pump laser wavelength, and provides a feasible technical scheme and device for outputting new wavelength laser of the diamond Raman laser and improving the conversion efficiency. BRIEF DESCRIPTION OF DRAWINGS

[0023] In order to more clearly illustrate the technical solutions in the application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description are some embodiments of the application, and other drawings can be obtained by those skilled in the art without creative labor.

[0024] Figure 1 is a structural schematic diagram of a diamond crystal multi-phonon intrinsic absorption band control device provided by an embodiment of the application;

[0025] Figure 2 is a structural schematic diagram of another diamond crystal multi-phonon intrinsic absorption band control device provided by an embodiment of the application;

[0026] Figure 3 is a structural schematic diagram of still another diamond crystal multi-phonon intrinsic absorption band control device provided by an embodiment of the application;

[0027] Figure 4 is a flow chart of a transmittance control method provided by an embodiment of the application. DETAILED DESCRIPTION

[0028] In order to make the purposes, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present application.

[0029] Figure 1 A structural schematic diagram of a diamond crystal multi-phonon intrinsic absorption band regulation device is provided in the embodiments of the present application. The diamond crystal multi-phonon intrinsic absorption band regulation device in the embodiments comprises a diamond crystal 1, a multi-phonon absorption band regulation module 2, and a transmittance regulation module.

[0030] The diamond crystal 1 comprises two oppositely parallel stress application surfaces 11 and two oppositely arranged light transmission end surfaces 12. The shape of the diamond crystal 1 is not limited, which can be a hexahedron, an octahedron or other irregular shapes. When the diamond crystal is a hexahedron, the two oppositely arranged light transmission end surfaces are perpendicular to the two oppositely parallel stress application surfaces. When the diamond crystal is an octahedron, the two oppositely arranged light transmission end surfaces are adjacent to or spaced apart from the two oppositely parallel stress application surfaces. When the diamond crystal is an irregular shape, the two oppositely arranged light transmission end surfaces are not the same end surfaces as the two oppositely parallel stress application surfaces.

[0031] The multi-phonon absorption band regulation module 2 is used to regulate the vibration mode of the diamond crystal 1, thereby regulating the multi-phonon combination mode, so as to control the range of the multi-phonon intrinsic absorption band of the diamond crystal 1. The multi-phonon absorption band regulation module 2 comprises a multifunctional stresser 21, a diamond anvil 1 and a diamond anvil 2 which are communicatively connected; the multifunctional stresser 21 is arranged on the side of the diamond anvil away from the stress application surface; the multifunctional stresser 21 can apply stress and sense the size of the stress according to the received stress signal; the diamond anvil 1 and the diamond anvil 2 are arranged on the stress application surface 11; the diamond anvil 1 and the diamond anvil 2 are used to transmit the stress applied by the multifunctional stresser 21 to the diamond crystal 1, so as to regulate the vibration mode of the diamond crystal 1.

[0032] The transmittance regulation module is used to regulate the transmittance of the pump laser in the diamond crystal 1, reduce the absorption of the pump laser, and increase the energy of the pump laser passing through the diamond crystal, and comprises a wide-tunable laser source 31, a split-beam monitor 32, a first detector 33, a central controller 34 and a second detector 35 which are communicatively connected.

[0033] The wide-tuning laser source 31 is used to emit the pump laser 311, and the wavelength of the pump laser can be controlled in a wide range according to requirements by the central controller 34.

[0034] The light-splitting monitor 32 splits the pump laser emitted by the wide-tuning laser source 31 according to a preset light-splitting ratio to generate first light-splitting 321 and second light-splitting 322, and the preset light-splitting ratio can be controlled by the central controller 34; the first light-splitting 321 is transmitted to the first detector 33, and after being converted into a monitoring signal by the first detector 33, is transmitted to the central controller 34; after penetrating the diamond crystal 1, the second light-splitting 322 is transmitted to the second detector 35, and after being converted into a detection signal by the second detector 35, is transmitted to the central controller 34.

[0035] The central controller 34 controls the wavelength of the pump laser emitted by the wide-tuning laser source 31, the ratio of the first light-splitting and the second light-splitting of the light-splitting monitor 32 according to preset parameters, and outputs the stress signal to the multifunctional stressor 21, thereby controlling the vibration mode of the diamond crystal 1 to further control the multi-phonon combination mode and control the multi-phonon intrinsic absorption band of the diamond crystal 1. The central controller 34 receives the monitoring signal and the detection signal, calculates the real-time transmittance of the pump laser according to the preset light-splitting ratio, compares the real-time transmittance with the preset transmittance, generates a stress control signal, and transmits the stress control signal to the multifunctional stressor 21 to further control the vibration mode of the diamond crystal 1 to control the range of the multi-phonon intrinsic absorption band, until the difference between the real-time transmittance and the preset transmittance is within the difference range of the preset transmittance, so as to achieve the goal of reducing the absorption of the pump laser and improving the conversion efficiency.

[0036] The diamond crystal multi-phonon intrinsic absorption band control device of the embodiment of the application controls the vibration mode of the diamond crystal through the multi-phonon control module, thereby controlling the multi-phonon combination mode in the diamond crystal to control the range of the multi-phonon intrinsic absorption band. The light-splitting monitor splits the pump laser into first light-splitting and second light-splitting according to a preset light-splitting ratio, uses the first light-splitting as a monitoring signal and the second light-splitting as a detection signal, the central controller calculates the transmittance of the pump laser according to the monitoring signal, the detection signal and the preset light-splitting ratio, and outputs a stress control signal to the multifunctional stressor to feedback control the range of the multi-phonon intrinsic absorption band, so as to finally achieve the goal of reducing the absorption of the pump laser and increasing the transmittance of the pump laser, thereby providing a feasible technology for expanding new wavelengths of diamond Raman lasers and improving conversion efficiency.

[0037] In some embodiments, the multi-phonon absorption band regulation module 2 can include a stress shaper, which is attached between the diamond anvil 1, the diamond crystal 1, and the diamond anvil 2, for adjusting the magnitude and direction of the stress applied to the diamond crystal 1. The stress shaper can be, for example, a copper sheet, boron nitride, or sodium chloride, which adjusts the direction of the stress and the magnitude of the stress in the direction by uniformly shaping and directionally shaping the stress transmitted by the diamond anvil.

[0038] In some embodiments, the multi-phonon absorption band regulation module 2 can include a stress protector, which is disposed between the diamond anvil 1 and the diamond anvil 2, on the side of the light transmission surface of the diamond crystal 1. The tensile and compressive fracture stress of the stress protector is slightly weaker than that of the diamond crystal 1. When the stress protector is broken, an electrical signal is transmitted to the central controller 34, which transmits a stop signal to the multifunctional stressor 21, and the multifunctional stressor 21 stops applying stress, thereby protecting the diamond crystal 1 from being damaged.

[0039] In some embodiments, the transmittance regulation module can further include a beam shaper, which is optically coaxially disposed on the optical path of the pump laser emitted by the wide-tunable laser source 31, for regulating the beam waist, divergence angle, polarization state, phase, and amplitude of the pump laser; or, the beam shaper is optically coaxially disposed on the optical path of the first light splitter 321, for regulating the beam waist, divergence angle, polarization state, and phase of the first light splitter 321; or, the beam shaper is optically coaxially disposed on the optical path of the second light splitter 322, for regulating the beam waist, divergence angle, polarization state, and phase of the second light splitter 322. The specific structure of the beam shaper is not limited in the present application, and can be set according to actual needs by those skilled in the art.

[0040] In some embodiments, the light splitter monitor 32 can split the wavefront, amplitude, power, and energy of the pump laser according to the preset light splitting ratio, which can be continuously changed according to the regulation of the central controller 34.

[0041] In some embodiments, the wavelength of the pump laser emitted by the wide-tunable laser source 31 can be continuously tuned according to the regulation of the central controller 34, with a wavelength coverage range of 2 μm ~ 15 μm and a tuning accuracy of ≤ 10 nm, to meet the requirements of pump laser tuning accuracy and Raman laser wavelength.

[0042] In some embodiments, the first detector 33 and the second detector 35 are wavefront detectors, energy detectors, power detectors, or interferometers according to the light splitting of the light splitting monitor 32.

[0043] In some embodiments, the range of the multi-phonon intrinsic absorption band of the diamond crystal 1 is wherein, is the Raman shift of the diamond under stress The relationship between the stress and is wherein, is the Raman shift of the diamond crystal without stress, and a and b are stress constants.

[0044] In some embodiments, the stress constants a and b can be obtained from experiments and theoretical fitting, wherein a = 517 ± 4 GPa and b = 764 ± 14 GPa. In a specific embodiment, when a = 517 GPa and b = 764 GPa, the error between the experimental value and the theoretical calculation value of the range of the multi-phonon intrinsic absorption band is ≤ 5%.

[0045] The present application also provides a transmittance control method, which comprises:

[0046] Firstly, the parameters of the central controller 34 are set, including the pump laser wavelength, the preset light splitting ratio, the preset transmittance of the pump laser wavelength, and the preset transmittance difference value. The central controller 34 controls the output of the pump laser wavelength and the ratio of the first light splitting 321 and the second light splitting 322 of the wide-tunable laser source 31 in sequence according to the set parameters, and outputs a stress signal to the multifunctional stressor 21.

[0047] Secondly, the multifunctional stressor 21 receives the stress signal and applies stress. The stress is applied to the diamond crystal 1 through the diamond anvil cell, which controls the vibration mode of the diamond crystal 1 and further controls the range of the multi-phonon intrinsic absorption band. The wide-tunable laser source 31 emits the pump laser, which is split into the first light splitting 321 and the second light splitting 322 by the light splitting monitor 32. The first light splitting 321 is transmitted to the first detector 33, which converts the first light splitting 321 into a monitoring signal and transmits it to the central controller 34. The second light splitting 322 penetrates the diamond crystal 1 and is transmitted to the second detector 35, which converts the second light splitting 322 into a detection signal and transmits it to the central controller 34.

[0048] The third step is that the central controller 34 receives the monitoring signal and the detection signal, calculates the real-time transmittance of the pump laser according to the preset light splitting ratio, compares the real-time transmittance with the preset transmittance, and obtains a real-time transmittance difference value.

[0049] The fourth step is that the central controller 34 outputs a stress control signal to the multifunctional stressor 21 according to the difference between the real-time transmittance difference value and the preset transmittance difference value, and repeats the second step, the third step and the fourth step until the real-time transmittance difference value is less than or equal to the preset transmittance difference value, and finally obtains the transmittance of the pump laser that meets the requirements, so as to reduce the absorption of the pump laser wavelength and improve the conversion efficiency by controlling the range of the multi-phonon intrinsic absorption band of the diamond crystal 1.

[0050] The transmittance control method provided by the application can accurately control the multi-phonon intrinsic absorption band of the diamond crystal, reduce the absorption of the pump laser, increase the transmittance of the pump laser and control the transmittance in real time, and provides a new solution for controlling the range of the intrinsic absorption band of the diamond crystal, and provides a feasible technology for expanding the wavelength of the diamond Raman laser and improving the conversion efficiency.

[0051] The diamond crystal multi-phonon intrinsic absorption band control device and the real-time transmittance control method provided by the application will be described below through specific embodiments.

[0052] Embodiment 1

[0053] The first diamond crystal multi-phonon intrinsic absorption band control device and the transmittance control method provided by the embodiment are shown in the device as shown in the figure. Figure 1 The diamond crystal 1 of the embodiment is a six-surface cuboid with a size of 2*2*7 mm3, and the standard Raman frequency shift is 1332.5 cm-1. Two opposite 2*7 mm2 surfaces 11 are stress application surfaces, and two opposite parallel 2*7 mm2 surfaces 12 are light transmission surfaces.

[0054] The multi-phonon absorption band control module 2 is used for controlling the vibration mode of the diamond crystal, so as to control the multi-phonon combined absorption, so as to control the range of the multi-phonon intrinsic absorption band of the diamond crystal. It includes a multifunctional stressor 21, a diamond anvil 1 and a diamond anvil 2. The multifunctional stressor 21 can apply stress and sense the size of the stress according to the received stress signal. The diamond anvil 1 and the diamond anvil 2 are used for transmitting the stress applied by the multifunctional stressor 21 to the diamond crystal 1, and controlling the vibration mode of the diamond crystal 1.

[0055] The transmittance regulation module is used for regulating the transmittance of the pump laser in the diamond crystal 1, reducing the absorption of the pump laser, and increasing the energy of the pump laser passing through the diamond crystal, and comprises a wide-tunable laser source 31, a light splitting monitor 32, a first detector 33, a central controller 34, and a second detector 35 which are communicatively connected.

[0056] The diamond crystal multi-phonon intrinsic absorption band regulation device provided by the embodiment is regulated according to the transmittance regulation method, and the regulation process is as follows:

[0057] First, the parameters of the central controller 34 are set, the parameters including that the pump laser wavelength is 4.5 μm, the preset light splitting ratio is 4:6, the preset transmittance of the pump laser wavelength is 65%, and the preset transmittance difference value is ±1%. The central controller 34 regulates the wide-tunable laser source 31 to emit the 4.5 μm pump laser according to the set parameters, the ratio of the first light splitting 321 and the second light splitting 322 is 4:6, and the multi-phonon intrinsic absorption band range is 4.5 μm-5.5 μm. and When a=517 GPa and b=764 GPa, the stress is calculated to be 685 GPa, and the output stress signal is transmitted to the multifunctional stressor 21.

[0058] Secondly, the multifunctional stressor 21 receives the stress signal to apply stress, the stress is applied to the diamond crystal 1 through the diamond anvil cell, and the vibration mode of the diamond crystal 1 is regulated; the wide-tunable laser source 31 emits the 4.5 μm pump laser with an energy of 10 mW, and after the pump laser is split by the light splitting monitor 32 according to the preset light splitting ratio 4:6, 4 mW of the first light splitting 321 and 6 mW of the second light splitting 322 are generated, the first light splitting 321 is transmitted to the first detector 33, the first detector 33 converts the 4 mW of the first light splitting 321 into a monitoring signal, and then transmits the monitoring signal to the central controller 34, the second light splitting 322 penetrates the diamond crystal 1, and then transmits the second light splitting 322 to the second detector 35, and the remaining 3 mW, the second detector 35 converts the 3 mW of the second light splitting 322 into a detection signal, and then transmits the detection signal to the central controller 34.

[0059] Then, the central controller 34 receives the monitoring signal and the detection signal, and calculates the real-time transmittance of the pump laser to be 50% according to the preset light splitting ratio 4:6, and obtains the real-time transmittance difference value to be 15% compared with the preset transmittance 65%.

[0060] Finally, the central controller 34 compares the real-time transmittance difference value 15% with the difference value 1% of the preset transmittance difference value, and generates a stress control signal to the multifunctional stresser 21. The above steps are repeated until the second probe 35 detects a second split detection signal of 3.89 mW. The central controller 34 calculates that the real-time transmittance is 64.83%, and the real-time transmittance difference value is 0.17% compared with the preset transmittance 65%. The difference value is less than the difference value 1% of the preset transmittance difference value. At this time, the transmittance of the pump laser that meets the demand reaches the range of the intrinsic multi-phonon absorption band of the diamond crystal 1, reduces the absorption of the pump laser wavelength, and improves the conversion efficiency.

[0061] Embodiment 2

[0062] The second diamond crystal multi-phonon intrinsic absorption band control device provided in this embodiment is shown in FIG. 2. The structure of the device provided in this embodiment is basically the same as that of the device provided in Embodiment 1, and the difference is that: Figure 2

[0063] 1. The control module 3 includes a beam shaper including a focal length f100 mm positive lens 361 and a focal length f200 mm positive lens 362. The beam waist of the pump laser emitted by the wide-tunable laser source 31 is expanded to a smaller divergence angle.

[0064] 2. The pump laser emitted by the wide-tunable laser source 31 has a wavelength of 6.2 μm and an energy of 1 mJ.

[0065] 3. The preset split ratio of the split monitor is 5:5, and the energy of the pump laser is split.

[0066] 4. The preset transmittance is 70%, and the difference value of the preset transmittance is ±1%.

[0067] 5. The multi-phonon absorption band control module 2 includes a stress shaper 23 made of copper sheet, which uniformly shapes the stress of the diamond anvil.

[0068] The diamond crystal multi-phonon intrinsic absorption band control device provided in this embodiment is based on the transmittance control method, and the adjustment process is the same as that of Embodiment 1, and the difference is that:

[0069] The central controller 34 calculates an output stress signal of 142.6 GPa and transmits it to the multifunctional stresser 21.

[0070] After the pump laser passes through the split monitor 32 according to the preset split ratio 5:5, the first split 321 and the second split 322 of 0.5 mJ are generated.

[0071] ​After the above regulation, the second detector 35 finally detects a second light splitting detection signal of 0.349 mJ, and the central controller 34 calculates a real-time transmittance of 69.8%, which is compared with the preset transmittance of 70% to obtain a real-time transmittance difference value of 0.02%, which is less than the difference value of 1% of the preset transmittance difference value. At this time, the transmittance of the pump laser that meets the demand reaches the range of the regulation of the multi-phonon intrinsic absorption band of the diamond crystal 1, and the purpose of reducing the absorption of the pump laser wavelength and improving the conversion efficiency is achieved.

[0072] Embodiment 3

[0073] This embodiment provides a second diamond crystal multi-phonon intrinsic absorption band regulation device, as shown in Figure 3 It should be noted that, in order to show the position of the stress protector, the embodiment of the present application is attached Figure 3 and Figure 1 , Figure 2 from different perspectives. The structure of the device provided in this embodiment is basically the same as that of the device provided in Embodiment 1, and the difference lies in that:

[0074] 1. The multi-phonon absorption band regulation module 2 comprises a stress protector 24, and the tensile and compressive fracture stress of the stress protector is slightly weaker than the diamond crystal 1.

[0075] 2. The pump laser wavelength emitted by the wide-tunable laser source 31 is 2.5 μm, and the energy is 1 mJ.

[0076] 3. The preset transmittance is 60%, and the difference value of the preset transmittance is ±1%.

[0077] The diamond crystal multi-phonon intrinsic absorption band regulation device provided in this embodiment is regulated according to the transmittance regulation method, and the adjustment process is the same as that of Embodiment 1, and the difference lies in that:

[0078] The central controller 34 calculates an output stress signal of 4096.7 GPa and transmits it to the multifunctional stressor 21. The multifunctional stressor 21 receives the stress signal and applies stress, and the stress is applied to the diamond crystal 1 through the diamond anvil cell. When the stress reaches 2500 GPa, the stress protector 24 breaks and transmits an electrical signal to the central controller 34, and the central controller 34 transmits a stop signal to the multifunctional stressor 21, and the multifunctional stressor 21 stops applying stress, protecting the diamond crystal 1 from being damaged. At this time, the given wavelength corresponds to excessive stress, and the transmittance regulation cannot be realized by regulating the multi-phonon intrinsic absorption band of the diamond crystal through stress.

Claims

1. A device for regulating multi-phonon intrinsic absorption bands of diamond crystals, characterized in that: include: The diamond crystal comprises two relatively parallel stress-applying surfaces and two relatively parallel light-transmitting end surfaces; a multi-phonon absorption band control module, configured to control the multi-phonon combination mode by controlling the vibration mode of the diamond crystal, so as to control the range of the multi-phonon intrinsic absorption band of the diamond crystal, wherein the multi-phonon absorption band control module comprises a multifunctional stressor and a diamond anvil in communication connection; the diamond anvil is attached to the stress-applying surface, and the multifunctional stressor is attached to a side of the diamond anvil facing away from the stress-applying surface; The stress applied by the multifunctional stressor is transmitted to the diamond crystal through the diamond anvil to regulate the vibration mode of the diamond crystal; The transmittance control module is used to control the transmittance of the pump laser in the diamond crystal, including a wide-tuned laser source, a spectroscopic monitor, a first detector, a central controller, and a second detector connected in communication; the wide-tuned laser source is used to emit the pump laser, and the wavelength of the pump laser is tunable in a wide range; the spectroscopic monitor splits the pump laser according to a preset spectroscopic ratio to generate a first spectroscopic beam and a second spectroscopic beam, and the first spectroscopic beam is received by the first detector and converted into a monitoring signal and transmitted to the central controller; the second spectroscopic beam penetrates the diamond crystal and is transmitted to the second detector, and is converted into a detection signal and transmitted to the central controller. The central controller controls the stress applied by the multifunctional stressor, the wavelength of the pump laser, and the ratio of the first and second split beams according to preset parameters, and calculates the real-time transmittance of the pump laser according to the received monitoring signal, the detection signal, and the preset split beam ratio. The central controller compares the real-time transmittance with the preset transmittance to generate a stress control signal, which is transmitted to the multifunctional stressor to control the vibration mode of the diamond crystal and the range of the multi-phonon intrinsic absorption band to meet the preset transmittance; the range of the multi-phonon intrinsic absorption band is The relationship between stress P and Δω is: Where a and b are stress constants, ω0 = 1332.5 cm -1 is the Raman frequency shift of diamond under no stress, Δω is the Raman frequency shift of diamond under stress; the value ranges of a and b are: a=517±4GPa, b=764±14GPa.

2. The diamond crystal multi-phonon intrinsic absorption band control device according to claim 1, characterized in that: The multi-phonon absorption band regulation module includes a stress shaper, which is placed between the diamond anvil and the diamond crystal and is used to adjust the magnitude and direction of the stress applied to the diamond crystal.

3. The diamond crystal multi-phonon intrinsic absorption band control device according to claim 1, characterized in that: The multi-phonon absorption band regulation module includes a stress protector, which is placed between the diamond anvil cells and on the side of the light-transmitting surface of the diamond crystal.

4. The device for regulating multi-phonon intrinsic absorption bands of diamond crystals according to any one of claims 1 to 3, characterized in that: The transmittance control module further includes a beam shaper for controlling the beam waist, divergence angle, polarization state, phase, and amplitude of the laser beam emitted by the wide-tunable laser source.

5. The diamond crystal multi-phonon intrinsic absorption band control device according to any one of claims 1 to 3, characterized in that: The spectroscopic monitor splits the wavefront, amplitude, power and energy of the pump laser according to a splitting ratio, and the splitting ratio can be continuously changed.

6. The device for regulating multi-phonon intrinsic absorption bands of diamond crystals according to any one of claims 1 to 3, characterized in that: The laser wavelength range of the wide-tunable laser source covers 2 μm to 15 μm, and the tuning accuracy is ≤10 nm.

7. The device for regulating multi-phonon intrinsic absorption bands of diamond crystals according to any one of claims 1 to 3, characterized in that: The first detector and the second detector may be a wavefront detector, an energy detector, a power detector, or an interferometer.

8. A transmittance control method, used in the diamond crystal multi-phonon intrinsic absorption band control device according to any one of claims 1 to 7, characterized in that: The transmittance control method includes: Setting parameters of the central controller, including a pump laser wavelength, a preset splitting ratio, a preset transmittance of the pump laser wavelength, and a preset transmittance difference value, wherein the central controller sequentially controls the output of the pump laser wavelength, the ratio of the first splitting and the second splitting by the wide-tunable laser source according to the set parameters, and outputs a stress signal to be transmitted to the multifunctional stressor; The multifunctional stressor receives the stress signal and applies stress, and the applied stress is applied to the diamond crystal through the diamond anvil, thereby regulating the vibration mode of the diamond crystal and further regulating the range of the multi-phonon intrinsic absorption band; the wide-tunable laser source emits the pump laser, and the pump laser is split by the spectroscopic monitor to generate a first split light and a second split light, the first split light is transmitted to the first detector shown, converted into a monitoring signal, and then transmitted to the central controller, and the second split light penetrates the diamond crystal and is transmitted to the second detector, converted into the detection signal and transmitted to the central controller; The central controller receives the monitoring signal and the detection signal, calculates the real-time transmittance of the pump laser in real time according to the preset splitting ratio, and compares it with the preset transmittance to obtain a real-time transmittance difference value; The central controller outputs a stress control signal to the multifunctional stress device according to the difference between the real-time transmittance difference value and the preset transmittance difference value, and repeats the second, third and fourth steps until the real-time transmittance difference value is less than or equal to the preset transmittance difference value, and finally obtains the transmittance of the pump laser that meets the requirements.

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