Macroenergy disc laser hot mirror effect control system

Abstract

The invention provides a macro-energy disc laser hot mirror effect control system comprising a pump beam shaping system used for outputting shaped pump laser; the disc crystal generates large-energy laser under the excitation of the pump beam shaping system; the first detector is used for detecting heat distribution on the front surface of the disc crystal; the second detector is used for detecting the temperature change of the side surface of the disc crystal and / or the height change of the heated expansion of the disc crystal and the heat distribution of the side surface; wherein the first detector and the second detector are colloidal quantum dot mercury telluride infrared detectors, and the first detector and the second detector are respectively connected with a control system. And the control system adaptively regulates and controls the pump laser output by the pump beam shaping system based on detection results of the first detector and the second detector, so that the hot mirror effect of the disc crystal is controlled, and the optical performance of the macro-energy disc laser is further improved.

Description

Technical Field

[0001] The present disclosure relates to the field of laser technology infrared imaging detectors, and in particular to a high-energy disk laser thermal mirror effect control system. Background Art

[0002] The application of solid-state laser systems with high output power, high efficiency and good beam quality has been promoted in industry and laboratories. Since Giesen et al. proposed the laser diode end-pumped disk TD (thin-disk) laser in 1993, it has further promoted the development of compact and efficient solid-state lasers. The composition thickness of the disk solid-state laser gain medium (disk crystal) is about 100-200μm, which is much smaller than the radius of the gain medium. It is very easy to attach to a heat sink system such as diamond, and has a compact optical structure, high photoelectric conversion efficiency and extremely high heat dissipation efficiency. However, as the output power of the disk laser increases, even such a thin disk crystal in the high-energy disk laser will still change the refractive index of the disk due to heat, expand due to heat, and bend due to heat, resulting in a thermal mirror effect, which will cause the laser in the cavity to shift and the laser photoelectric conversion efficiency to decrease. Therefore, solving the thermal mirror effect of the disk crystal is one of the hot issues in breaking through high-power and high-energy solid-state lasers. The thermal infrared band covers the mid-infrared and long-infrared bands, so high-performance and high-precision infrared detectors are very important for measuring the thermal mirror effect of disk lasers. Traditional infrared detectors are usually made of bulk semiconductor materials such as mercury cadmium telluride, type II superlattice, and indium antimonide, and require complex flip-chip bonding methods to synthesize, which limits the detector specifications, resolution, and signal transmission. However, the emerging liquid nano-semiconductor crystals (colloidal quantum dots CQD) have quantum confinement effects.

[0003] Therefore, the present invention realizes direct silicon-based circuit board coupling integration through chemical solution synthesis, and the colloidal quantum dot detector has been developed from a single-point detector to an imaging focal plane array, which can more accurately observe the thermal distribution and thermal changes on the surface of the disk crystal in the disk laser. Summary of the invention

[0004] The purpose of the present disclosure is to provide a high-energy disk laser thermal mirror effect control system that can solve at least one of the above-mentioned technical problems. The specific solution is as follows:

[0005] The present invention provides a high-energy disk laser thermal mirror effect control system, which is characterized by comprising:

[0006] The pump beam shaping system 5 is used to output shaped pump laser light and adjust the pump light to suppress the thermal mirror effect of the disk crystal 3 .

[0007] The disk crystal 3 generates high-energy laser light under the stimulation of the pump beam shaping system 5;

[0008] A first detector 10 is used to detect the heat distribution on the front side of the disk crystal 3;

[0009] The second detector 20 is used to detect the temperature change of the side surface of the disc crystal 3 and / or the height change of the disc crystal 3 due to thermal expansion and the heat distribution of the side surface;

[0010] Among them, the first detector 10 and the second detector 20 are colloidal quantum dot mercury telluride infrared detectors, and the first detector 10 and the second detector 20 are respectively connected to the control system 4. The control system 4 adaptively regulates the pump laser output by the pump beam shaping system 5 based on the detection results of the first detector 10 and the second detector 20, thereby controlling the thermal mirror effect of the disk crystal 3.

[0011] In some embodiments, the colloidal quantum dot mercury telluride infrared detector includes the following layers stacked in sequence: a substrate layer 11, a transparent conductive electrode layer 12, an electron transport layer 13, a mercury telluride quantum dot layer 14, a hole transport layer 15, a metal electrode layer 16, and an encapsulation layer 17.

[0012] In some embodiments, the substrate layer 11 is a glass substrate, which provides mechanical support and stability;

[0013] The transparent conductive electrode layer 12 is an indium tin oxide (ITO) conductive electrode layer, which is used as an electrode to allow photons to pass through and collect electrons;

[0014] The electron transport layer 13 is a barium titanate electron transport layer, which is used for efficiently transmitting electrons;

[0015] The mercury telluride quantum dot layer 14 is a HgCl2-doped mercury telluride colloidal quantum dot layer, which is used for core light absorption and carrier generation;

[0016] The hole transport layer 15 is an indium tungstate hole transport layer, which is used for efficiently transporting holes;

[0017] The metal electrode layer 16 is an Au electrode layer, which serves as another electrode to form a closed circuit and collect holes.

[0018] In some embodiments, the imaging focal plane array of the colloidal quantum dot mercury telluride infrared detector is 1280×1024, configured to achieve 4×10 10 Jones's average peak-to-peak detection rate.

[0019] In some embodiments, the pump beam shaping system 5 comprises:

[0020] A laser diode pump light source 54, used to output pump laser;

[0021] A first Fourier transform lens 53, used to adjust the pump laser into a frequency domain space;

[0022] A spatial light modulator 52, used to adjust the phase and amplitude of the pump laser in the frequency domain;

[0023] The second Fourier transmission lens 51 is used to adjust the pump laser in the frequency domain space to the real domain space.

[0024] In some embodiments, the colloidal quantum dot mercury telluride infrared detector and the pump beam shaping system 5 form an adaptive system to achieve high-precision measurement of the thermal mirror effect on the surface of the disk crystal 3 and further modulate the focal length of the pump beam to suppress the thermal mirror effect.

[0025] In some embodiments, the equation for the change in the refractive index of the disk crystal 3 due to temperature is:

[0026]

[0027] Wherein, T0(x, y, z) is the temperature of the disk crystal 3 before pumping, and T(x, y, z) is the dynamic temperature of the disk crystal 3 after pumping. is the coefficient of change of the refractive index of the disk crystal 3 due to heat.

[0028] In some embodiments, the thermal focal length of the disk crystal 3 satisfies the following relationship:

[0029]

[0030] Wherein P is the absorbed heat power, K(T) is the thermal conductivity of the disk crystal 3 as it changes with temperature, w is the beam waist radius of the pump laser, α is the absorption coefficient, and L is the thickness of the disk crystal 3.

[0031] In some embodiments, the coefficient of thermal change of the refractive index of the disk crystal 3 is 9×10 -6 K -1 .

[0032] In some embodiments, the disc crystal 3 has a thickness of 100-200 μm.

[0033] In some embodiments, the colloidal quantum dot mercury telluride infrared detector is formed by the following method:

[0034] The inorganic mercury salt and elemental tellurium required for the synthesis of quantum dots are dissolved in oleylamine as a reaction solvent; the mixed solution is placed in a glass bottle and heated on a hot plate. After the temperature of the hot plate reaches 100°C, trioctylphosphine is injected using a pipette;

[0035] Use a pipette to add β-mercaptoethanol to the mercury telluride quantum dots, and remove the lower layer of liquid by ultrasonication for 1 minute;

[0036] Transferring mercury telluride quantum dots from a nonpolar solvent to a polar solvent;

[0037] The polarity of quantum dots is regulated, and liquid phase method is used for doping to introduce electrons or holes. HgCl2 or (NH4)2S is added to the intrinsic quantum dot solution to prepare n-type and / or p-type mercury telluride quantum dots.

[0038] In some embodiments, the polar solvent is a dimethylformamide solution.

[0039] Compared with the prior art, the above solution of the embodiment of the present disclosure has at least the following beneficial effects:

[0040] The mercury telluride quantum dot detector in the present invention has high device resolution, wide spectral control range, high average peak ratio detection rate, high conversion efficiency of preparation technology, low cost and small minimum noise equivalent temperature difference, and is suitable for monitoring the thermal mirror effect of gain medium in laser or disk crystal in disk laser. The mercury telluride infrared detector made of colloidal quantum dots by liquid phase synthesis chemical method can efficiently observe the changes of thermal mirror effect of disk crystal in disk laser.

[0041] This system is equipped with a pump wavefront shaping system and a mercury telluride quantum dot detector to form an adaptive combination. Through the mercury telluride quantum dot detector and pump wavefront shaping, the detected data is fed back to the pump light shaping system to adjust the pump light to achieve the suppression effect of the disk crystal, thus realizing a high-precision measurement and suppression system for the thermal mirror effect of the gain medium of a high-energy disk laser. The disk gain medium is the key to the disk laser generating a high-quality beam, so this application can further improve the manufacturing process of high-energy disk lasers. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] The drawings herein are incorporated into the specification and constitute a part of the specification, showing embodiments consistent with the present disclosure, and together with the specification, are used to explain the principles of the present disclosure. Obviously, the drawings described below are only some embodiments of the present disclosure, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. In the drawings:

[0043] Figure 1 It is a structural diagram of the thermal mirror effect control system of a large energy disk laser.

[0044] Figure 2 It is the structural distribution of the device of colloidal quantum dot mercury telluride infrared detector.

[0045] Figure 3is the spectral response of the colloidal quantum dot mercury telluride infrared detector. DETAILED DESCRIPTION

[0046] In order to make the purpose, technical scheme and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all 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.

[0047] The terms used in the embodiments of the present application are only for the purpose of describing specific embodiments, and are not intended to limit the present application. The singular forms "a", "said" and "the" used in the embodiments of the present application and the appended claims are also intended to include plural forms, unless the context clearly indicates other meanings, and "multiple" generally includes at least two.

[0048] It should be understood that the term "and / or" used in this article is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0049] As used herein, the words "if" and "if" may be interpreted as "at the time of" or "when" or "in response to determining" or "in response to detecting", depending on the context. Similarly, the phrases "if it is determined" or "if (stated condition or event) is detected" may be interpreted as "when it is determined" or "in response to determining" or "when detecting (stated condition or event)" or "in response to detecting (stated condition or event)", depending on the context.

[0050] It should also be noted that the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a product or system including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such a product or system. In the absence of more restrictions, the elements defined by the sentence "comprises a ..." do not exclude the existence of other identical elements in the product or system including the elements.

[0051] The optional embodiments of the present disclosure are described in detail below with reference to the accompanying drawings.

[0052] The present invention provides a high-energy disk laser thermal mirror effect control system, comprising: a pump beam shaping system 5, a disk crystal 3, a first detector 10 and a second detector 20.

[0053] Specifically, in this embodiment, the pump beam shaping system 5 is used to output a shaped pump laser, and the pump light is adjusted to suppress the thermal mirror effect of the disk crystal 3. The pump beam shaping system includes a plurality of pump source components, and the plurality of pump source components are respectively parallel to the disk crystal 3. The pump light component is used to shape the pump laser. The shaped pump light is perpendicular to the disk crystal 3, which is beneficial to the absorption of the pump laser by the disk laser.

[0054] Specifically, in this embodiment, the disk crystal 3 generates high-energy laser under the stimulation of the pump beam shaping system 5. The composition thickness of the disk crystal is 100-200 μm, which is much smaller than the radius of the gain medium. It is very easy to attach to the heat sink system 2 such as diamond, and has a compact optical structure, high photoelectric conversion efficiency and extremely high heat dissipation efficiency. As the output power of the disk laser increases, the extremely thin disk in the high-energy disk laser will still change the refractive index of the disk due to heat, expand and bend due to heat, produce a thermal mirror effect, and cause the laser in the cavity to shift and the laser photoelectric conversion efficiency to decrease. The pump wavefront shaping system and the mercury telluride quantum dot detector form an adaptive combination to adjust the pump light to achieve the suppression effect of the disk crystal.

[0055] Specifically, in this embodiment, the first detector 10 is used to detect the heat distribution on the front side of the disc crystal 3, and feed back the detected heat distribution map to the computer control system 4 for monitoring the surface temperature of the disc crystal 3; the second detector 20 is used to detect the temperature change on the side of the disc crystal 3 and / or the height change of the disc crystal 3 due to thermal expansion and the heat distribution on the side of the disc crystal 3; the first detector 10 and the second detector 20 work simultaneously, and feed back the measured heat distribution map and the change of crystal focal length caused by the thermal mirror effect to the computer control system 4, and the control system guides the pump light shaper 5 to output the pump light beam to achieve different heat distribution regulation.

[0056] In this embodiment, the first detector 10 and the second detector 20 are colloidal quantum dot mercury telluride infrared detectors, and the first detector 10 and the second detector 20 are respectively connected to the control system 4. The control system 4 adaptively controls the pump laser output by the pump beam shaping system 5 based on the detection results of the first detector 10 and the second detector 20, thereby controlling the thermal mirror effect of the disk crystal 3, and realizing real-time thermal monitoring of the disk crystal in the high-energy disk laser and regulation of the thermal mirror effect.

[0057] In this embodiment, the pump beam shaping system 5 includes: a laser diode pump light source 54, which is used to output pump laser; a first Fourier transform lens 53, which is used to adjust the pump laser to the frequency domain space; a spatial light modulator 52, which is used to adjust the phase and amplitude of the pump laser in the frequency domain space; a second Fourier transmission lens 51, which is used to adjust the pump laser in the frequency domain space to the real domain space.

[0058] The pump light shaping system 5 first performs a Fourier transform through the first Fourier transform lens 53 to convert the light beam in the real domain space to the frequency domain space (Fourier space). In the Fourier space, the spatial frequency information of the light beam is clearly separated, which is convenient for precise modulation. In the frequency domain space, the spatial light modulator 52 is used to adjust the phase of each pixel point to control the interference and diffraction characteristics of the light beam in the real domain space, thereby changing the focus and shape of the light beam. By controlling the transmittance of each area and adjusting the intensity distribution of the light beam in different areas, the overall shape and mode of the light beam are further affected. It is then converted to the real domain space through the second Fourier transmission lens 51. This modulation can convert the original fundamental mode Gaussian beam TEM 00 Conversion to higher order modes TEM nn (n represents different order modes, and the adjustment range is 0-6), thereby changing the energy distribution of the light beam and optimizing the heat distribution, thereby suppressing the focal length f generated by the thermal mirror effect.

[0059] In this embodiment, the equation for the change of the refractive index of the disk crystal 3 under temperature is:

[0060]

[0061] Wherein, T0(x, y, z) is the temperature of the disk crystal 3 before pumping, and T(x, y, z) is the dynamic temperature of the disk crystal 3 after pumping. is the coefficient of change of the refractive index of the disk crystal 3 due to heat.

[0062] Furthermore, the change in the refractive index and thickness of the disk crystal 3 due to thermal expansion can produce an optical path difference OPD along the paraxial z direction, which is expressed as follows:

[0063] OPD=∫Δn(x,y,z)dz

[0064] Furthermore, according to the diffraction theory of scalar field, the optical path difference OPD caused by the thermal effect is regarded as similar to the phase of the lens in geometric optics, and the thermal focal length of the disk crystal 3 satisfies the following relationship:

[0065]

[0066] Wherein P is the absorbed heat power, K(T) is the thermal conductivity of the disk crystal 3 as it changes with temperature, w is the beam waist radius of the pump laser, α is the absorption coefficient, and L is the thickness of the disk crystal 3.

[0067] Furthermore, the coefficient of thermal change of the refractive index of the disk crystal 3 is 9×10 -6 K -1 .

[0068] In some embodiments, Figure 2 As shown, the colloidal quantum dot mercury telluride infrared detector includes the following layers stacked in sequence: a substrate layer 11, a transparent conductive electrode layer 12, an electron transport layer 13, a mercury telluride quantum dot layer 14, a hole transport layer 15, a metal electrode layer 16, and an encapsulation layer 17.

[0069] Specifically, in this embodiment, the substrate layer 11 is a glass substrate, which provides mechanical support and stability;

[0070] The transparent conductive electrode layer 12 is an indium tin oxide (ITO) conductive electrode layer, which is used as an electrode to allow photons to pass through and collect electrons;

[0071] The electron transport layer 13 is a barium titanate electron transport layer, which is used to efficiently transport electrons, block holes, and reduce recombination;

[0072] The mercury telluride quantum dot layer 14 is a HgCl2-doped mercury telluride colloidal quantum dot layer, which is used for core light absorption and carrier generation, and determines the photoelectric performance of the device;

[0073] The hole transport layer 15 is an indium tungstate hole transport layer, which is used to efficiently transport holes, block electrons, and reduce electron-hole recombination;

[0074] The metal electrode layer 16 is an Au electrode layer, which serves as another electrode to form a closed circuit and collect holes;

[0075] The encapsulation layer 17 is an epoxy resin encapsulation layer, which is used to protect the device, extend the life of the device, and maintain the stability of the performance of the colloidal quantum dot mercury telluride infrared detector.

[0076] Specifically, in this embodiment, the colloidal quantum dot mercury telluride infrared detector is used to convert the optical signal into a thermal signal and transmit it to the computer control system 4 to accurately display the surface temperature of the disk crystal 3 .

[0077] Specifically, in this embodiment, the imaging focal plane array of the colloidal quantum dot mercury telluride infrared detector is 1280×1024, which is configured to achieve 4×10 10Jones's average peak ratio detection rate, high resolution, high average peak ratio detection rate and small minimum noise equivalent temperature difference can more accurately observe the thermal distribution and thermal changes on the surface of the disk crystal, and realize the thermal mirror effect monitoring of the gain medium in the laser or the disk crystal in the disk laser.

[0078] Specifically, in this embodiment, the colloidal quantum dot mercury telluride infrared detector is formed by the following method:

[0079] The inorganic mercury salt and elemental tellurium required for quantum dot synthesis are dissolved in oleylamine as a reaction solvent; the required inorganic mercury salt HgCl2 and elemental tellurium are weighed and dissolved in oleylamine. In an anhydrous and oxygen-free glove box, a magnetic stirrer is used to heat to 120°C and continuously stirred until all solids are completely dissolved to form a uniform mixed solution.

[0080] Place the mixed solution in a glass bottle and heat it on a hot plate. Slowly heat it to 100°C under argon protection. After the hot plate temperature reaches 100°C, keep it for 30 minutes to ensure the uniformity of the solution. Use an anhydrous and oxygen-free pipette to slowly inject trioctylphosphine. The injection rate needs to be controlled at 1 ml per minute to ensure the stable growth and size uniformity of the quantum dots. According to the emission wavelength of the required quantum dots, the temperature and time of the reaction are precisely controlled. High temperature and long reaction time will cause the quantum dots to increase in size and the emission wavelength to red shift. The practical temperature control system accurately adjusts the reaction temperature, and the growth of the quantum dots can be observed by infrared spectroscopy or other online monitoring methods.

[0081] Furthermore, in order to achieve the doping of mercury telluride quantum dots, ligand exchange is required, and the specific steps are:

[0082] β-Mercaptoethanol was added to the mercury telluride quantum dots using a pipette, and the lower layer of liquid was removed by ultrasonication for 1 minute. The doping of mercury telluride quantum dots was achieved by a mixed liquid phase ligand exchange method.

[0083] Transferring mercury telluride quantum dots from a nonpolar solvent to a polar solvent;

[0084] The polarity of quantum dots is regulated, and doping is performed by liquid phase method to introduce electrons or holes. HgCl2 or (NH4)2S is added to the intrinsic quantum dot solution to prepare n-type and / or p-type mercury telluride quantum dots. The mercury telluride quantum dot (HgTe CQDs) detector has high device resolution, high average peak ratio detection rate and small minimum noise equivalent temperature difference. It is suitable for monitoring the thermal mirror effect of gain media in lasers or disk crystals in disk lasers, and solves the defects of traditional infrared detectors such as complex flip-chip bonding methods, limited detector specifications, resolution and signal transmission.

[0085] In this embodiment, the polar solvent is dimethylformamide solution.

[0086] The structure of the prepared colloidal quantum dot mercury telluride detector is as follows: Figure 2 As shown. Electrons are transferred to the transparent conductive electrode through the ETL, while holes are transferred to the metal electrode through the HTL, forming a current signal. By measuring the change in current, the intensity and wavelength of the incident light can be detected, realizing the photoelectric detection function. The spectral response of the prepared colloidal quantum dot mercury telluride detector measured at room temperature is shown in Figure 3 As shown in the results, the colloidal quantum dot mercury telluride detector achieves 4×10 10 Jones's average peak ratio detection rate can more accurately observe the thermal distribution and thermal changes on the surface of the disk crystal in the disk laser. The controlled pump light shaping system and the high-precision colloidal quantum dot mercury telluride detector form an adaptive system, which can realize real-time thermal monitoring of the disk crystal in the high-energy disk laser and control of the thermal mirror effect.

[0087] The following is a specific example of preparing a colloidal quantum dot mercury telluride (HgTe) detector. The entire process needs to be carried out under anhydrous and oxygen-free conditions to ensure the quality and performance of the quantum dots.

[0088] Materials preparation:

[0089] ① Mercury telluride (HgTe) precursor (inorganic precursor): mercury chloride (HgCl2): 0.1 mol (about 22.2 g); 0.1 mol (about 125.6 g).

[0090] ②Solvents and ligands: Oleylamine (OA) as reaction solvent: 50 ml; Tri-n-octylphosphine (TOP) as injection agent: 10 ml; β-mercaptoethanol (β-ME) as ligand replacement agent: 5 ml; Dimethylformamide (DMF) as polar solvent: 100 ml.

[0091] ③ Doping reagents: Mercuric chloride (HgCl2): used to prepare n-type quantum dots, 0.005 mol (about 1.11 g); ammonium thiocyanate ((NH4)2S): used to prepare p-type quantum dots, 0.005 mol (about 0.195 g).

[0092] Equipment preparation:

[0093] ① Anhydrous and oxygen-free operating equipment (such as a glove box under argon or nitrogen protection)

[0094] ②High purity glass reaction bottle (100 ml capacity)

[0095] ③Hot plate and temperature control system

[0096] ④Pipette gun (waterless type)

[0097] ⑤Ultrasonic cleaner

[0098] ⑥Separatory funnel

[0099] Preparation steps:

[0100] 1. Precursor dissolution

[0101] The required 0.1 mol of inorganic mercury salt HgCl2 (about 22.2 g) and 0.1 mol of elemental tellurium (about 125.6 g) were weighed and dissolved in 50 ml of oleylamine. In an anhydrous and oxygen-free glove box, a magnetic stirrer was used to heat to 120°C and continuously stirred until all solids were completely dissolved to form a uniform precursor solution.

[0102] 2. Heating reaction

[0103] The homogeneous precursor solution was transferred to a high-purity glass reaction bottle. The reaction bottle was placed on a heated magnetic stirrer and slowly heated to 100°C under argon protection and maintained at this temperature for 30 minutes to ensure the homogeneity of the solution.

[0104] 3. Injection of trioctylphosphine

[0105] Under the reaction condition of maintaining 100°C, 10 ml of trioctylphosphine (TOP) was slowly injected using an anhydrous and oxygen-free pipette. The injection rate should be controlled at 1 ml per minute to ensure the stable growth and size uniformity of quantum dots.

[0106] 4. Control reaction temperature and time

[0107] Depending on the emission wavelength of the desired quantum dots, precisely control the temperature and time of the reaction. Higher temperatures and longer reaction times usually result in an increase in the size of the quantum dots, which in turn causes the emission wavelength to move toward the red shift. Maintain a low temperature (100°C) and a short reaction time (30 minutes). Appropriately increase the temperature (to 150°C) and extend the reaction time (1 hour). Use a temperature control system to precisely adjust the reaction temperature, and observe the growth of the quantum dots by infrared spectroscopy or other online monitoring methods.

[0108] 5. Anhydrous and oxygen-free environment

[0109] During the entire synthesis process, ensure that the reaction system is carried out under the protection of argon or nitrogen, and use anhydrous desiccants (such as molecular sieves) to cover all reaction vessels to prevent the introduction of moisture and oxygen. After the synthesis is completed, the reaction bottle is sealed and continued to cool to room temperature under an inert atmosphere.

[0110] 6. Ligand Exchange

[0111] In order to achieve the doping of mercury telluride quantum dots, a ligand exchange step is required: take the quantum dot solution after the reaction is completed and slowly add 5 ml of β-mercaptoethanol (β-ME). Use an ultrasonic cleaner to ultrasonicate at 60% power for 1 minute to promote the replacement of oleylamine ligands. After centrifugation (8000rpm, 10 minutes), carefully take the supernatant to remove unreacted oleylamine and impurities. Add the supernatant to 100 ml of dimethylformamide (DMF) and stir well to transfer the quantum dots from the non-polar solvent to the polar solvent. Use a centrifuge (8000rpm, 10 minutes) to separate the impurities that have not been transferred, and take the supernatant as the quantum dot solution in the polar solvent.

[0112] 7. Doping control

[0113] The quantum dots are doped by the liquid phase method to introduce electrons or holes to prepare n-type or p-type mercury telluride quantum dots:

[0114] ①Preparation of n-type quantum dots

[0115] In the DMF solution, 1.11 g of mercuric chloride (HgCl2) was slowly added while continuously stirring for 30 minutes to ensure that the mercury ions were uniformly incorporated into the quantum dot lattice to provide additional electrons.

[0116] ②Preparation of p-type quantum dots

[0117] In another portion of DMF solution, 0.195 g of ammonium thiocyanate ((NH4)2S) was slowly added while stirring for 30 minutes to allow sulfur ions to be incorporated into the quantum dot lattice to form holes.

[0118] 8. Post-processing and characterization

[0119] After centrifuging the doped quantum dot solution (8000 rpm, 10 minutes), the supernatant was discarded and fresh DMF was added for repeated washing at least three times to remove unreacted reagents and byproducts. The washed quantum dots were precipitated in dry DMF and fully dispersed to ensure uniformity.

Claims

1. A high-energy disk laser thermal mirror effect control system, characterized in that: include: A pump beam shaping system (5), used for outputting shaped pump laser light; The disk crystal (3) generates high-energy laser light under the stimulation of the pump beam shaping system (5); A first detector (10) for detecting the heat distribution on the front side of the disk crystal (3); A second detector (20) is used to detect temperature changes on the side of the disk crystal (3) and / or height changes of the disk crystal (3) due to thermal expansion and heat distribution on the side; The first detector (10) and the second detector (20) are colloidal quantum dot mercury telluride infrared detectors, and the first detector (10) and the second detector (20) are respectively connected to a control system (4). The control system (4) adaptively regulates the pump laser output by the pump beam shaping system (5) based on the detection results of the first detector (10) and the second detector (20), thereby controlling the thermal mirror effect of the disk crystal (3).

2. The high energy disk laser thermal mirror effect control system according to claim 1, characterized in that: The colloidal quantum dot mercury telluride infrared detector comprises the following layers stacked in sequence: a substrate layer (11), a transparent conductive electrode layer (12), an electron transport layer (13), a mercury telluride quantum dot layer (14), a hole transport layer (15), a metal electrode layer (16), and a packaging layer (17).

3. The high energy disk laser thermal mirror effect control system according to claim 2, characterized in that: The substrate layer (11) is a glass substrate, which provides mechanical support and stability; The transparent conductive electrode layer (12) is an indium tin oxide (ITO) conductive electrode layer, which is used as an electrode to allow photons to pass through and collect electrons; The electron transport layer (13) is a barium titanate electron transport layer, which is used for efficiently transporting electrons; The mercury telluride quantum dot layer (14) is a HgCl2-doped mercury telluride colloidal quantum dot layer, which is used for core light absorption and carrier generation; The hole transport layer (15) is an indium tungstate hole transport layer, which is used for efficiently transporting holes; The metal electrode layer (16) is an Au electrode layer, which serves as another electrode to form a closed circuit and collect holes.

4. The high energy disk laser thermal mirror effect control system according to claim 1, characterized in that: The imaging focal plane array of the colloidal quantum dot mercury telluride infrared detector is 1280×1024, which is configured to achieve 4×10 10 Jones's average peak-to-peak detection rate.

5. The high energy disk laser thermal mirror effect control system according to claim 1, characterized in that: The pump beam shaping system (5) comprises: A laser diode pump light source (54) for outputting pump laser light; A first Fourier transform lens (53) for adjusting the pump laser into a frequency domain space; A spatial light modulator (52) for adjusting the phase and amplitude of the pump laser in the frequency domain; The second Fourier transmission lens (51) is used to adjust the pump laser in the frequency domain space to the real domain space.

6. The high energy disk laser thermal mirror effect control system according to claim 1, characterized in that: The equation for the change of the refractive index of the disk crystal (3) under temperature is: Wherein, T0(x, y, z) is the temperature of the disk crystal (3) before pumping, and T(x, y, z) is the dynamic temperature of the disk crystal (3) after pumping light. is the coefficient of change of the refractive index of the disk crystal (3) due to heat.

7. The high energy disk laser thermal mirror effect control system according to claim 6, characterized in that: The thermal focal length of the disk crystal (3) satisfies the following relationship: Wherein P is the absorbed heat power, K(T) is the thermal conductivity of the disk crystal (3) as it changes with temperature, w is the beam waist radius of the pump laser, α is the absorption coefficient, and L is the thickness of the disk crystal (3).

8. The high energy disk laser thermal mirror effect control system according to claim 6, characterized in that: The coefficient of change of the refractive index of the disk crystal (3) due to heat is 9×10 -6 K -1 .

9. The high energy disk laser thermal mirror effect control system according to claim 1, characterized in that: The colloidal quantum dot mercury telluride infrared detector is formed by the following method: The inorganic mercury salt and elemental tellurium required for the synthesis of quantum dots are dissolved in oleylamine as a reaction solvent; the mixed solution is placed in a glass bottle and heated on a hot plate. After the temperature of the hot plate reaches 100°C, trioctylphosphine is injected using a pipette; Use a pipette to add β-mercaptoethanol to the mercury telluride quantum dots, and remove the lower layer of liquid by ultrasonication for 1 minute; Transferring mercury telluride quantum dots from a nonpolar solvent to a polar solvent; The polarity of quantum dots is regulated, and liquid phase method is used for doping to introduce electrons or holes. HgCl2 or (NH4)2S is added to the intrinsic quantum dot solution to prepare n-type and / or p-type mercury telluride quantum dots.

10. The high energy disk laser thermal mirror effect control system according to claim 9, characterized in that: The polar solvent is dimethylformamide solution.

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