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

Abstract

The invention provides a diamond crystal multi-phonon intrinsic absorption band regulation and control device and a transmittance regulation and control method. The device comprises a diamond crystal, a multi-phonon absorption band regulation and control module and a transmittance regulation and control module. According to the multi-phonon intrinsic absorption band regulation and control device based on the diamond crystal, stress is applied to the diamond crystal, the vibration mode of the diamond crystal is regulated and controlled, and multi-phonon combination of the diamond crystal is controlled, so that the range of the multi-phonon intrinsic absorption band of the diamond crystal is regulated and controlled, absorption of pumping laser is reduced, and the transmittance of the pumping laser is increased; and the stress applied to the diamond crystal is regulated and controlled by combining a real-time transmittance regulation and control method, so that the transmittance of the pumping laser passing through the diamond crystal is controlled to meet the use requirement. The range of the multi-phonon intrinsic absorption band of the diamond crystal can be regulated and controlled, so that the absorption of the pumping laser wavelength is reduced, the barrier generated by the intrinsic absorption band is broken, and the new diamond Raman laser wavelength with high beam quality and high power is output.

Description

Technical Field

[0001] The present invention relates to the field of laser technology, and in particular to a diamond crystal multi-phonon intrinsic absorption band control device and a transmittance control method. Background Art

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

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

[0004] The present invention provides a diamond crystal multi-phonon intrinsic absorption band control device and a real-time transmittance control method, which provide a new feasible technical solution for controlling the range of the diamond crystal multi-phonon intrinsic absorption band. The range of the multi-phonon intrinsic absorption band can be controlled by the diamond crystal multi-phonon intrinsic absorption band control device and the real-time transmittance control method, thereby increasing the transmittance of the pump laser wavelength and reducing absorption. The intrinsic absorption band "barrier" is broken, providing a feasible technical solution and device for diamond Raman laser to output new wavelength laser and improve conversion efficiency.

[0005] The first aspect of the present invention provides a device for regulating multi-phonon intrinsic absorption bands of diamond crystals, comprising: A diamond crystal, comprising two relatively parallel stress-applying surfaces and two relatively parallel light-transmitting end surfaces; A multi-phonon absorption band control module is used to control the multi-phonon combination mode by controlling the vibration mode of the diamond crystal to control the range of the multi-phonon intrinsic absorption band of the diamond crystal. The multi-phonon absorption band control module includes a multifunctional stressor and a diamond anvil that are communicatively connected; the diamond anvil is attached to the stress application surface, and the multifunctional stressor is attached to the side of the diamond anvil away from the stress application surface; the stress applied by the multifunctional stressor is transmitted to the diamond crystal through the diamond anvil to control 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 that are communicatively connected; the wide-tuned laser source is used to emit the pump laser, and the wavelength of the pump laser is tunable within 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 converted into a detection signal. The detection signal is transmitted to the central controller; the central controller adjusts the stress applied by the multifunctional stressor, the wavelength of the pump laser, and the ratio of the first beam splitting to the second beam splitting 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 beam splitting ratio. The central controller compares the real-time transmittance with the preset transmittance to generate a stress control signal, and the stress control signal 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.

[0006] According to one embodiment of the present invention, the range of the multi-phonon intrinsic absorption band is ,stress and The relationship is , where a and b are stress constants, is the Raman frequency shift of diamond in the absence of stress, is the Raman frequency shift of diamond under stress.

[0007] According to one embodiment of the present invention, the value ranges of a and b are: a=517±4 GPa, b=764±14 GPa.

[0008] According to an embodiment of the present invention, the multi-phonon absorption band regulation module includes a stress shaper disposed between the diamond anvil and the diamond crystal, and used to adjust the magnitude and direction of the stress applied to the diamond crystal.

[0009] According to an embodiment of the present invention, the multi-phonon absorption band regulation module includes a stress protector, and the stress protector is placed between the diamond anvils and on the side of the light-transmitting surface of the diamond crystal.

[0010] According to an embodiment of the present invention, 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.

[0011] According to an embodiment of the present invention, 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.

[0012] According to an embodiment of the present invention, the laser wavelength range of the wide-tunable laser source covers 2 μm to 15 μm, and the tuning accuracy is ≤10 nm.

[0013] According to one embodiment of the present invention, the first detector and the second detector may be a wavefront detector, an energy detector, a power detector, or an interferometer.

[0014] A second aspect of the present invention provides a transmittance control method for the diamond crystal multi-phonon intrinsic absorption band control device as described above, the transmittance control method comprising: Setting parameters of the central controller, wherein 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. The central controller sequentially adjusts the output of the pump laser wavelength, the ratio of the first splitting and the second splitting by the wide-tuned laser source according to the setting parameters, and outputs a stress signal to be transmitted to the multifunctional stress device; The multifunctional stressor receives the stress signal and applies stress, and the applied stress is applied to the diamond crystal through the diamond anvil, so as to regulate the vibration mode of the diamond crystal and further regulate the range of the multi-phonon intrinsic absorption band; the wide-tuned 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 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.

[0015] The present invention provides a diamond crystal multi-phonon intrinsic absorption band control device and a real-time transmittance control method. The vibration mode of the diamond crystal is controlled by the multi-phonon absorption band control module, and then the multi-phonon combination mode in the diamond crystal is controlled to control the range of the diamond crystal multi-phonon intrinsic absorption band 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 transmittance index is monitored in real time so that the transmittance meets the use requirements. The technical solution of the invention breaks the "barrier" of the intrinsic absorption band, solves the problem that the laser wavelength within the intrinsic absorption band of the diamond crystal cannot be output or used as the pump laser wavelength, and provides a feasible technical solution and device for the diamond Raman laser to output a new wavelength laser and improve the conversion efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0017] Figure 1 It is a schematic structural diagram of a diamond crystal multi-phonon intrinsic absorption band control device provided by an embodiment of the present invention; Figure 2 It is a schematic structural diagram of another diamond crystal multi-phonon intrinsic absorption band regulating device provided by an embodiment of the present invention; Figure 3 It is a structural schematic diagram of another diamond crystal multi-phonon intrinsic absorption band regulating device provided by an embodiment of the present invention; Figure 4 It is a flow chart of a transmittance control method provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0018] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0019] Figure 1 A schematic diagram of the structure of a diamond crystal multi-phonon intrinsic absorption band control device provided in an embodiment of the present invention. The diamond crystal multi-phonon intrinsic absorption band control device of this embodiment comprises a diamond crystal 1, a multi-phonon absorption band control module 2, and a transmittance control module.

[0020] The diamond crystal 1 includes two relatively parallel stress-applying surfaces 11, and two relatively parallel light-transmitting end surfaces 12. There is no limitation on the shape of the diamond crystal 1, which may be a hexahedron, an octahedron or other irregular shapes. When the diamond crystal is a hexahedron, the two relatively parallel light-transmitting end surfaces are in a perpendicular relationship to the two relatively parallel stress-applying surfaces. When the diamond crystal is an octahedron, the two relatively parallel light-transmitting end surfaces are in an adjacent or spaced relationship to the two relatively parallel stress-applying surfaces. When the diamond crystal is an irregular shape, the two relatively parallel light-transmitting end surfaces are different end surfaces from the two relatively parallel stress-applying surfaces.

[0021] The multi-phonon absorption band control module 2 is used to control the vibration mode of the diamond crystal 1, thereby controlling the multi-phonon combination mode to control the range of the multi-phonon intrinsic absorption band of the diamond crystal 1. The multi-phonon absorption band control module 2 includes a multifunctional stressor 21, a diamond anvil 1, and a diamond anvil 2 that are communicatively connected; the multifunctional stressor 21 is attached to the side of the diamond anvil away from the stress application surface; the multifunctional stressor 21 can apply stress and sense the magnitude of stress according to the received stress signal. The diamond anvil 1 and the diamond anvil 2 are attached to the stress application surface 11; the diamond anvil 1 and the diamond anvil 2 are used to transmit the stress applied by the multifunctional stressor 21 to the diamond crystal 1 to control the vibration mode of the diamond crystal 1.

[0022] The transmittance control module is used to control 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, including a communication-connected wide-tuned laser source 31, a spectroscopic monitor 32, a first detector 33, a central controller 34, and a second detector 35.

[0023] The wide-tunable laser source 31 is used to emit the pump laser 311 , and the wavelength of the pump laser can be controlled by the central controller 34 to be tuned within a wide range according to demand.

[0024] The spectroscopic monitor 32 splits the pump laser emitted by the wide-tuned laser source 31 according to a preset spectroscopic ratio to generate a first spectroscopic beam 321 and a second spectroscopic beam 322, and the preset spectroscopic ratio can be controlled by the central controller 34; the first spectroscopic beam 321 is transmitted to the first detector 33, and after being converted into a monitoring signal by the first detector 33, it is transmitted to the central controller 34; the second spectroscopic beam 322 penetrates the diamond crystal 1 and is transmitted to the second detector 35, and after being converted into a detection signal by the second detector 35, it is transmitted to the central controller 34.

[0025] The central controller 34 sequentially adjusts the wavelength of the pump laser emitted by the wide-tuned laser source 31, the ratio of the first and second beamsplitting of the beamsplitting monitor 32, and outputs the stress signal to the multifunctional stressor 21 according to preset parameters, including the wavelength of the pump laser, the preset beam splitting ratio of the beam splitting monitor, the preset transmittance of the pump laser wavelength, and the preset transmittance difference value, and then adjusts the vibration mode of the diamond crystal 1 to further adjust 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 beam splitting ratio, compares it with the preset transmittance, generates a stress control signal, and transmits the stress control signal to the multifunctional stressor 21, further adjusts 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 preset transmittance difference value range, so as to achieve the goal of reducing the pump laser absorption and improving the conversion efficiency.

[0026] The diamond crystal multi-phonon intrinsic absorption band control device of the embodiment of the present invention controls the vibration mode of the diamond crystal through the multi-phonon control module, and then controls the multi-phonon combination mode in the diamond crystal to control the range of the multi-phonon intrinsic absorption band. The pump laser is divided into a first beam and a second beam according to a preset beam ratio through a spectroscopic monitor. The first beam is used as a monitoring signal and the second beam is used 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 beam ratio, and outputs a stress control signal to the multi-functional stressor to feedback and control the range of the multi-phonon intrinsic absorption band, thereby finally achieving the purpose of reducing the absorption of the pump laser and increasing the transmittance of the pump laser, providing a feasible technology for expanding new wavelengths and improving conversion efficiency of diamond Raman lasers.

[0027] In some embodiments, the multi-phonon absorption band regulation module 2 may include a stress shaper, which is placed between the diamond anvil 1, the diamond crystal 1, and the diamond anvil 2 to adjust the magnitude and direction of the stress applied to the diamond crystal 1. The stress shaper may be, for example, a copper sheet, boron nitride, and sodium chloride, and the direction and magnitude of the stress in the direction are adjusted by uniformly shaping and directionally shaping the stress transmitted by the diamond anvil.

[0028] In some embodiments, the multi-phonon absorption band regulation module 2 may include a stress protector, which is placed between the diamond anvil 1 and the diamond anvil 2, on the side of the light-transmitting surface of the diamond crystal 1. The tensile and compressive fracture stresses of the stress protector are slightly weaker than those of the diamond crystal 1. When the stress protector breaks, an electrical signal is transmitted to the central controller 34, and the central controller 34 transmits a stop signal to the multifunctional stressor 21. The multifunctional stressor 21 stops applying stress to protect the diamond crystal 1 from damage.

[0029] In some embodiments, the transmittance control module may further include a beam shaper, which is optically coaxially placed on the optical line of the wide-tuned laser source 31 emitting the pump laser, and controls the beam waist, divergence angle, polarization state, phase, and amplitude of the pump laser; or, the beam shaper is optically coaxially placed on the optical line of the first beam splitter 321, and controls the beam waist, divergence angle, polarization state, and phase of the first beam splitter 321; or, the beam shaper is optically coaxially placed on the optical line of the second beam splitter 322, and controls the beam waist, divergence angle, polarization state, and phase of the second beam splitter 322. The present invention does not limit the specific structure of the beam shaper, and those skilled in the art can set it according to actual needs.

[0030] In some embodiments, the spectroscopic monitor 32 can split the wavefront, amplitude, power, and energy of the pump laser according to the preset spectroscopic ratio, and the preset spectroscopic ratio can be continuously changed according to the regulation of the central controller 34 .

[0031] In some embodiments, the wavelength of the pump laser emitted by the wide-tunable laser source 31 can be continuously tuned according to the control of the central controller 34, with a wavelength coverage range of 2μm ~ 15μm and a tuning accuracy of ≤10nm to meet the requirements of pump laser tuning accuracy and Raman laser wavelength.

[0032] In some embodiments, the first detector 33 and the second detector 35 may be wavefront detectors, energy detectors, power detectors, or interferometers according to the spectroscopy of the spectroscopy monitor 32 .

[0033] In some embodiments, the multi-phonon intrinsic absorption band of the diamond crystal 1 ranges from ,in, For stress Raman frequency shift of diamond under stress and The relationship is ,in, is the Raman frequency shift of diamond crystal when there is no stress, and a and b are stress constants.

[0034] In some embodiments, the stress constants a and b can obtain a numerical range based on experimental and theoretical fitting, where a=517±4GPa, b=764±14GPa. In a specific embodiment, when a=517GPa and b=764GPa, the error between the experimental value and the theoretical calculated value of the range of the multi-phonon intrinsic absorption band is ≤5%.

[0035] The present invention also provides a transmittance control method, which comprises: The first step is to set the parameters of the central controller 34, which include the pump laser wavelength, the preset splitting ratio, the preset transmittance of the pump laser wavelength, and the preset transmittance difference value. The central controller 34 sequentially adjusts the output of the pump laser wavelength, the ratio of the first splitting 321 and the second splitting 322 by the wide-tuned laser source 31 according to the set parameters, and outputs a stress signal to be transmitted to the multifunctional stress device 21; In the second step, the multifunctional stress device 21 receives the stress signal and applies stress, and the stress is applied to the diamond crystal 1 through the diamond anvil, so as to adjust the vibration mode of the diamond crystal 1 and further adjust the multi-phonon intrinsic absorption band range; the wide-tuned laser source 31 emits the pump laser, and the pump laser is split by the spectroscopic monitor 32 to generate a first split light 321 and a second split light 322, and the first split light 321 is transmitted to the first detector 33 shown, and the first detector 33 converts the first split light 321 into a monitoring signal and transmits it to the central controller 34, and the second split light 322 penetrates the diamond crystal 1 and is transmitted to the second detector 35, and the second detector 35 converts the second split light 322 into a detection signal and transmits it to the central controller 34; In the third step, the central controller 34 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 the real-time transmittance with the preset transmittance to obtain a real-time transmittance difference value; In the fourth step, the central controller 34 outputs a stress control signal to the multifunctional stress device 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, thereby achieving the purpose of reducing the absorption of the pump laser wavelength and improving the conversion efficiency by regulating the range of the multi-phonon intrinsic absorption band of the diamond crystal 1.

[0036] The transmittance control method of the present invention, through repeated optimization feedback of the above steps, accurately controls the multi-phonon intrinsic absorption band of the diamond crystal, reduces the absorption of the pump laser, increases the transmittance of the pump laser and controls the transmittance in real time, providing a new solution for controlling the range of the intrinsic absorption band of the diamond crystal, and providing a feasible technology for expanding new wavelengths and improving conversion efficiency of diamond Raman lasers.

[0037] The diamond crystal multi-phonon intrinsic absorption band control device and the real-time transmittance control method of the present invention are described below through specific embodiments.

[0038] Example 1 This embodiment provides a first diamond crystal multi-phonon intrinsic absorption band control device and transmittance control method, the device is as follows Figure 1 As shown, the diamond crystal 1 of this embodiment is a hexagonal cuboid of 2*2*7 mm3, with a standard Raman frequency shift of 1332.5 cm-1, wherein two opposite 2*7 mm2 faces 11 are stress-applied faces, and two relatively parallel 2*7 mm2 faces 12 perpendicular thereto are light-transmitting faces.

[0039] The multi-phonon absorption band control module 2 is used to control the vibration mode of the diamond crystal, thereby controlling the multi-phonon combined absorption, so as to achieve the purpose of controlling the range of the multi-phonon intrinsic absorption band of the diamond crystal. It includes a multi-functional stressor 21, a diamond anvil 1, and a diamond anvil 2; the multi-functional stressor 21 can apply stress and sense the magnitude of stress according to the received stress signal. The diamond anvil 1 and the diamond anvil 2 are used to transmit the stress applied by the multi-functional stressor 21 to the diamond crystal 1, and control the vibration mode of the diamond crystal 1.

[0040] The transmittance control module is used to control 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, including a communication-connected wide-tuned laser source 31, a spectroscopic monitor 32, a first detector 33, a central controller 34, and a second detector 35.

[0041] The diamond crystal multi-phonon intrinsic absorption band control device provided in this embodiment has the following control process according to the transmittance control method: First, the parameters of the central controller 34 are set, wherein the parameters include that the pump laser wavelength is 4.5 μm, the preset 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 sequentially controls the wide-tuned laser source 31 to emit 4.5 μm pump laser according to the set parameters, the ratio of the first splitting 321 to the second splitting 322 is 4:6, and the multi-phonon intrinsic absorption band range is set according to the multi-phonon intrinsic absorption band range. and When a=517 GPa and b=764 GPa, the calculated stress is 685 GPa, and the output stress signal is transmitted to the multifunctional stress device 21 .

[0042] Secondly, the multifunctional stress device 21 receives the stress signal and applies stress, and the stress is applied to the diamond crystal 1 through the diamond anvil to regulate the vibration mode of the diamond crystal 1; the wide-tuned laser source 31 emits a 4.5 μm pump laser with an energy of 10 mW, and the pump laser is split by the spectroscopic monitor 32 according to a preset splitting ratio of 4:6 to generate a 4mW first split light 321 and a 6mW second split light 322, and the first split light 321 is transmitted to the first detector 33 shown, and the first detector 33 converts the 4mW first split light 321 into a monitoring signal and transmits it to the central controller 34, and the second split light 322 penetrates the diamond crystal 1 and is transmitted to the second detector 35, and 3mW is left, and the second detector 35 converts the 3mW second split light 322 into a detection signal and transmits it to the central controller 34; Then, the central controller 34 receives the monitoring signal and the detection signal, and calculates in real time the real-time transmittance of the pump laser as 50% according to the preset splitting ratio of 4:6, and compares it with the preset transmittance of 65%, obtaining a real-time transmittance difference of 15%.

[0043] Finally, the central controller 34 generates a stress control signal to the multifunctional stress device 21 based on the comparison between the real-time transmittance difference value 15% and the preset transmittance difference value 1%, and repeats the above steps until the second detector 35 finally detects a second spectroscopic detection signal of 3.89mW. The central controller 34 calculates the real-time transmittance to be 64.83%, and compares it with the preset transmittance 65%, and obtains a real-time transmittance difference value of 0.17%, which is less than the preset transmittance difference value of 1%. At this time, the transmittance of the pump laser meets the requirements, and the purpose of reducing the absorption of the pump laser wavelength and improving the conversion efficiency is achieved by adjusting the range of the multi-phonon intrinsic absorption band of the diamond crystal 1.

[0044] Example 2 This embodiment provides a second diamond crystal multi-phonon intrinsic absorption band control device, such as Figure 2 As shown, the structure of the device provided in this embodiment is basically the same as the structure of the device provided in Example 1, except that: 1. The control module 3 includes a beam shaper, including a positive lens 361 with a focal length of f100mm and a positive lens 362 with a focal length of f200mm, which expands the beam waist of the pump laser emitted by the wide-tuned laser source 31 to have a smaller divergence angle.

[0045] 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.

[0046] 3. The preset splitting ratio of the splitting monitor is 5:5, which splits the energy of the pump laser.

[0047] 4. The preset transmittance is 70%, and the preset transmittance difference is ±1%.

[0048] 5. The multi-phonon absorption band control module 2 includes a stress shaper 23 made of a copper sheet, which is used to homogenize and shape the stress of the diamond anvil.

[0049] The diamond crystal multi-phonon intrinsic absorption band control device provided in this embodiment is based on the transmittance control method, and the control process is the same as that of embodiment 1, except that: The central controller 34 calculates and outputs an output stress signal of 142.6 GPa and transmits it to the multifunctional stress device 21 .

[0050] After the pump laser is split by the splitting monitor 32 according to the preset splitting ratio of 5:5, a first split light 321 of 0.5 mJ and a second split light 322 of 0.5 mJ are generated.

[0051] After the above regulation, the second detector 35 finally detects a second spectroscopic detection signal of 0.349 mJ, and the central controller 34 calculates a real-time transmittance of 69.8%. Compared with the preset transmittance of 70%, the real-time transmittance difference is 0.02%, which is less than the preset transmittance difference of 1%. At this time, the transmittance of the pump laser meets the requirements, and the purpose of reducing the absorption of the pump laser wavelength and improving the conversion efficiency is achieved by regulating the range of the multi-phonon intrinsic absorption band of the diamond crystal 1.

[0052] Example 3 This embodiment provides a second diamond crystal multi-phonon intrinsic absorption band control device, such as Figure 3 It should be noted that, in order to facilitate the illustration of the position of the stress protector, the embodiment of the present invention is attached. Figure 3 and Figure 1 , Figure 2 The structure of the device provided in this embodiment is basically the same as that of the device provided in Embodiment 1, except that: 1. The multi-phonon absorption band regulating module 2 includes a stress protector 24 , and the tensile and compressive fracture stresses of the stress protector are slightly weaker than those of the diamond crystal 1 .

[0053] 2. The pump laser emitted by the wide-tunable laser source 31 has a wavelength of 2.5 μm and an energy of 1 mJ.

[0054] 3. The preset transmittance is 60%, and the preset transmittance difference is ±1%.

[0055] The diamond crystal multi-phonon intrinsic absorption band control device provided in this embodiment is based on the transmittance control method, and the control process is the same as that of embodiment 1, except that: The central controller 34 calculates and outputs an output stress signal of 4096.7 GPa and transmits it to the multifunctional stress device 21. The multifunctional stress device 21 receives the stress signal and applies stress, and the stress is applied to the diamond crystal 1 through the diamond anvil. When the stress reaches 2500 GPa, the stress protector 24 breaks and transmits an electrical signal to the central controller 34. The central controller 34 transmits a stop signal to the multifunctional stress device 21, and the multifunctional stress device 21 stops applying stress to protect the diamond crystal 1 from being damaged. At this time, the stress corresponding to the given wavelength is too large, and the transmittance regulation cannot be achieved by stress regulation of the multi-phonon intrinsic absorption band of the diamond crystal.

Claims

1. A diamond crystal multi-phonon intrinsic absorption band control device, characterized in that: include: A diamond crystal, comprising two relatively parallel stress-applying surfaces and two relatively parallel light-transmitting end surfaces; A multi-phonon absorption band control module is used to control the multi-phonon combination mode by controlling the vibration mode of the diamond crystal to control the range of the multi-phonon intrinsic absorption band of the diamond crystal. The multi-phonon absorption band control module includes a multifunctional stressor and a diamond anvil connected in communication; the diamond anvil is attached to the stress application surface, and the multifunctional stressor is attached to the side of the diamond anvil away from the stress application 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 that are communicatively connected; the wide-tuned laser source is used to emit the pump laser, and the wavelength of the pump laser is tunable within 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 converted into a detection signal. The detection signal is transmitted to the central controller; the central controller adjusts the stress applied by the multifunctional stressor, the wavelength of the pump laser, and the ratio of the first beam splitting to the second beam splitting 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 beam splitting ratio. The central controller compares the real-time transmittance with the preset transmittance to generate a stress control signal, and the stress control signal 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.

2. The diamond crystal multi-phonon intrinsic absorption band control device according to claim 1, characterized in that: The range of the multi-phonon intrinsic absorption band is ,stress and The relationship is , where a and b are stress constants, is the Raman frequency shift of diamond in the absence of stress, is the Raman frequency shift of diamond under stress.

3. The diamond crystal multi-phonon intrinsic absorption band control device according to claim 2, characterized in that: The value ranges of a and b are: a=517±4GPa, b=764±14GPa.

4. 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.

5. The diamond crystal multi-phonon intrinsic absorption band control device according to claim 1, characterized in that: The multi-phonon absorption band regulating module comprises a stress protector, and the stress protector is placed between the diamond anvils and on the side of the light-transmitting surface of the diamond crystal.

6. The diamond crystal multi-phonon intrinsic absorption band control device according to any one of claims 1 to 5, characterized in that: The transmittance control module also 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.

7. The diamond crystal multi-phonon intrinsic absorption band control device according to any one of claims 1 to 5, 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.

8. The diamond crystal multi-phonon intrinsic absorption band control device according to any one of claims 1 to 5, 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.

9. The diamond crystal multi-phonon intrinsic absorption band control device according to any one of claims 1 to 5, characterized in that: The first detector and the second detector may be a wavefront detector, an energy detector, a power detector, or an interferometer.

10. A transmittance control method, used in the diamond crystal multi-phonon intrinsic absorption band control device according to any one of claims 1 to 9, characterized in that: The transmittance control method comprises: Setting parameters of the central controller, wherein 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. The central controller sequentially adjusts the output of the pump laser wavelength, the ratio of the first splitting and the second splitting by the wide-tuned laser source according to the setting parameters, and outputs a stress signal to be transmitted to the multifunctional stress device; The multifunctional stressor receives the stress signal and applies stress, and the applied stress is applied to the diamond crystal through the diamond anvil, so as to regulate the vibration mode of the diamond crystal and further regulate the range of the multi-phonon intrinsic absorption band; the wide-tuned 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 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.

Images