Online in-situ low-temperature high-pressure ultrafast spectrum device, system and method thereof

Abstract

The invention provides an online in-situ low-temperature high-pressure ultrafast spectrum device, system and method. The high-pressure device comprises a cold shield with an optical window, a metal ring, a gasket, a first pressurization air bag, a second pressurization air bag, a pressurization metal column, a diamond anvil cell pressing cavity, a first temperature sensor, a second temperature sensor, a heat conduction base, a low-temperature thermostat and an air pressure controller. The on-line in-situ pressure calibration and imaging system comprises a continuous light laser, a high-pressure device, an on-line in-situ pressure optical component and an on-line in-situ pressure imaging system. The low-temperature high-pressure ultrafast pumping detection system comprises a femtosecond laser, an online in-situ pressure calibration and imaging system, a pumping detection optical component and a pumping detection imaging system. According to the invention, 6-325K temperature regulation under the high pressure of double-airbag pressure regulation is realized; on-line in-situ free pressure increasing and reducing adjustment and control at low temperature are achieved, and the pressure is continuously adjusted and controlled within the range of 0-80 GPa with the precision of 0.1 GPa; and online in-situ low-temperature and high-pressure ultrafast spectrum and ultrafast dynamic measurement is realized.

Description

Technical Field

[0001] The present invention belongs to the field of ultrafast spectroscopy, and in particular relates to an online in-situ low-temperature and high-pressure ultrafast spectroscopy device, a system and a method thereof. Background Art

[0002] Ultrafast spectroscopy is an important frontier in the study of non-equilibrium condensed matter physics. This technology is an important tool for studying ultrafast dynamic processes inside condensed matter. It also has the characteristics of extremely high resolution and sensitivity, non-destructiveness, and non-contactness of spectroscopy technology. Therefore, it has broad application prospects in basic research, materials science, industrial production, medical science and other fields. The most basic ultrafast spectroscopy technology is pump-probe technology. The main principle of this technology is to first irradiate the material with a beam of pump laser to pump the material into an excited state. After a certain delay, another laser beam or other detection means is used to detect the sample to obtain information such as multi-degree-of-freedom coupling and non-equilibrium relaxation of the sample in the excited state.

[0003] In order to study the physical properties of materials under different external conditions, external temperature and pressure control are important technical means to study physical properties. In pressure control, the online in-situ pressure regulation high-pressure system is of great significance for high-pressure spectral testing. The online in-situ pressure regulation means to adjust the pressure in the diamond anvil without moving the sample, avoiding the problem of low spectral signal stability and homing repeatability caused by removing the diamond anvil from the optical path. Among them, the airbag in-situ pressure regulation is a feasible online in-situ pressure regulation means. Nowadays, high-pressure systems compatible with spectral testing are concentrated in non-low-temperature online in-situ systems and non-airbag in-situ pressure regulation high-pressure systems. In non-low-temperature online in-situ systems, temperature control is not compatible, and spectral testing of low-temperature samples cannot be achieved. In non-airbag in-situ pressure regulation systems, each pressure adjustment requires the diamond anvil to be compressed by a motor or other means, which has low pressure control accuracy for the sample, and will affect some spectral tests that are sensitive to the test sample point and sample surface morphology, reducing the credibility of experimental data. Therefore, providing a high-pressure system and a testing method for in-situ pressure regulation of airbags at low temperatures that are compatible with spectral testing will help solve this series of low-temperature and high-pressure sample testing problems.

[0004] In high-voltage systems compatible with spectral testing, it is common to use non-airbag in-situ pressure regulation high-voltage technology in room temperature environment, but there are few airbag in-situ pressure regulation and low-temperature high-voltage and ultrafast pump detection technology. Among the existing technologies, some have realized low-temperature Brillouin scattering and in-situ high-pressure Raman spectroscopy testing with in-situ high pressure, some have realized high-pressure ultrafast spectroscopy testing with airbag pressure regulation at room temperature, and some have realized high-pressure low-temperature ultrafast spectroscopy testing with in-situ airbag pressure regulation. The airbag pressure regulation technology compatible with ultrafast spectroscopy testing is of great significance for studying the physical properties of substances at low temperature and high pressure, but the current technology has some difficult problems to solve: for example, the airbag pressure regulation device can only be operated at room temperature and cannot achieve pressure regulation at low temperature. For some quantum materials that have special physical properties only at low temperature and high pressure, ultrafast spectroscopy testing cannot be performed. In the high-pressure and low-temperature technology using airbag pressure regulation, free pressure increase and pressure reduction cannot be achieved, and the imaging quality is poor. So far, no device can achieve low-temperature pressure regulation ultrafast pump detection measurement with free pressure increase and pressure reduction.

[0005] Therefore, there are still some challenges in combining the cryogenic system and the airbag pressure regulation high-pressure system to achieve free temperature regulation and pressure increase and decrease, and to be applicable to the ultrafast pump detection system: How to make the high pressure compatible with the temperature control system? How to achieve free pressure increase and decrease in the cryogenic system? How to calibrate the pressure at low temperature? How to be compatible with ultrafast pump detection measurement? For the realization of low-temperature and high-pressure ultrafast pump detection at liquid nitrogen and liquid helium temperatures, the above problems need to be solved urgently. Summary of the invention

[0006] Therefore, the purpose of the present invention is to overcome the defects in the prior art and provide an online in-situ low-temperature and high-pressure ultrafast spectroscopy device, its system and method. In order to achieve a dual-airbag online in-situ high-pressure regulation technology with less impact on the sample point at low temperature, achieve free pressure increase and decrease with higher precision, achieve an online in-situ pressure calibration method at low temperature and high pressure, and achieve an ultrafast pump detection experiment at low temperature and high pressure.

[0007] Before describing the present invention, the terms used in this article are defined as follows:

[0008] The term "OPA" means: Optical Parametric Amplifier.

[0009] The term "BBO crystal" means: barium metaborate crystal.

[0010] The term "LBO crystal" refers to: lithium triborate crystal.

[0011] The term "KDP crystals" refers to: potassium dihydrogen phosphate crystals.

[0012] The term "CCD camera" refers to a digital camera with a charge-coupled device image sensor.

[0013] The term "CMOS camera" refers to a camera that is typically 10 times less sensitive to light than a CCD camera.

[0014] The term "Dewar" refers to: containers and tools for storing liquefied gases, used for low-temperature research and protecting crystal components, etc.

[0015] The term "DAC" refers to: Diamond Anvil Cell.

[0016] The term “on-site in situ” refers to the detection situation in which the sample position is kept fixed without leaving the optical path or rotating the sample. In English, it is called “on-site in situ”, that is, the detection is performed in real time in its original environment without moving or rotating the object being detected, thereby avoiding resetting errors, that is, avoiding the impact of movement, rotation or changes in the detection environment on the results.

[0017] The term "ultrafast spectroscopy" refers to a technology that uses ultrashort laser pulses to detect the dynamic changes of matter on an extremely short time scale. It is called Ultrafast Spectroscopy in English and can capture the physical and chemical changes of matter on extreme time scales such as picoseconds, femtoseconds, and attoseconds.

[0018] The term "high pressure" refers to a working pressure greater than 101.325 kPa in ultrafast spectroscopy online in-situ detection.

[0019] The term "low temperature" refers to an operating temperature below 25°C in ultrafast spectroscopy in-line in-situ detection.

[0020] To achieve the above-mentioned object, the first aspect of the present invention provides a low-temperature dual-airbag pressure regulating high-pressure device, the high-pressure device comprising: a cold shield with an optical window, a metal ring, a gasket, a first pressurized airbag, a second pressurized airbag, a pressurized metal column, a diamond anvil pressure chamber, a first temperature sensor, a second temperature sensor, a thermally conductive base, a low-temperature thermostat and a pressure controller; wherein:

[0021] The metal ring fixes the gasket, the first pressurized airbag, the second pressurized airbag, the pressurized metal column, the diamond anvil pressure chamber and the first temperature sensor on one side of the thermally conductive base;

[0022] The second temperature sensor is independent of the metal ring and is disposed on the other side of the heat-conducting base;

[0023] The thermally conductive base and the cold shield are fixed on the cryostat.

[0024] According to the first aspect of the present invention, the high-voltage device further comprises a heating coil, and the heating coil is arranged on the same side of the heat-conducting base as the second temperature sensor; wherein,

[0025] The first temperature sensor is located outside the diamond anvil cell;

[0026] The pressurized metal column is located between the gasket and the diamond anvil pressure chamber;

[0027] The first pressurized airbag and the second pressurized airbag are both connected to the air pressure controller;

[0028] The metal ring comprises a first metal ring and a second metal ring, wherein the first metal ring and the first gasket are preferably connected to the first pressurized airbag; and / or

[0029] The gasket includes a first gasket and a second gasket, and the second metal ring and the second gasket are preferably connected to the second pressurized airbag.

[0030] According to the first aspect of the present invention, the high-voltage device further comprises: a metal housing having another optical window, a vacuum pump for providing a vacuum environment, and a Dewar for providing a low-temperature environment; wherein,

[0031] The cold shield and the thermally conductive base are located in a space formed by the metal housing and the cryostat; and / or

[0032] The vacuum pump and the Dewar are connected to the cryostat;

[0033] Preferably, the low temperature environment of the high pressure device is 6 to 325K, more preferably 20 to 315K, and further preferably 40 to 300K;

[0034] Preferably, the high pressure of the high pressure device is 0 to 80 GPa, more preferably 5 to 70 GPa, and further preferably 10 to 60 GPa;

[0035] Preferably, the diamond anvil in the diamond anvil pressure chamber is a shortened diamond anvil; and / or

[0036] Preferably, the Dewar is selected from one or more of the following: a cryogenic liquid nitrogen tank, a liquid nitrogen Dewar, a liquid helium Dewar, more preferably a liquid nitrogen Dewar or a liquid helium Dewar, most preferably a liquid helium Dewar.

[0037] A second aspect of the present invention provides an online in-situ pressure calibration and imaging system, the online in-situ pressure calibration and imaging system comprising:

[0038] The low-temperature double-airbag pressure regulating high-pressure device described in the first aspect;

[0039] CW laser;

[0040] Online in-situ calibration of optical components; and

[0041] Online in-situ sample appearance imaging component;

[0042] Among them, the continuous light laser emits laser, which is focused on the ruby ​​of the high-voltage device through the optical path constructed by the online in-situ pressure calibration optical component. The optical path guides the reflected light to the online in-situ sample morphology imaging component to realize the detection and calibration of the pressure values ​​in the diamond anvil under different temperatures and pressures.

[0043] According to the second aspect of the present invention, the online in-situ pressure calibration and imaging system, wherein:

[0044] The wavelength of the continuous laser is selected from one or more of the following: 532nm, 633nm, 450nm, preferably 532nm or 633nm, most preferably 532nm;

[0045] The online in-situ pressure correction optical components are selected from one or more of the following: a semi-transparent and semi-reflective mirror, a reflector, a light source, a relay lens, a fiber coupler, and a telephoto microscope objective lens; and / or

[0046] The online in-situ sample appearance imaging component is selected from one or more of the following: a spectrometer, a camera, and a computer host;

[0047] Preferably, the telephoto microscope objective lens is selected from one or more of the following: a 5x telephoto microscope objective lens, a 10x telephoto microscope objective lens, a 20x telephoto microscope objective lens, a 50x telephoto microscope objective lens, more preferably a 10x telephoto microscope objective lens or a 20x telephoto microscope objective lens, most preferably a 20x telephoto microscope objective lens; and / or

[0048] Preferably, the camera is selected from one or more of the following: a CCD camera, a CMOS camera, a SLR camera, more preferably a CCD camera and / or a CMOS camera, most preferably a CCD camera.

[0049] A third aspect of the present invention provides a low temperature, high pressure, ultrafast pump detection system, the low temperature, high pressure, ultrafast pump detection system comprising:

[0050] The online in-situ pressure calibration and imaging system according to the second aspect;

[0051] Femtosecond lasers;

[0052] pump-probe optics; and

[0053] Pump-probe imaging components;

[0054] Among them, the femtosecond laser emits a femtosecond laser, which is divided into two beams of light through the optical path constructed by the pump-detection optical component, and is focused together into the low-temperature double-airbag pressure-regulating high-voltage device. The optical path guides the reflected light to the pump-detection imaging component, and the temperature and pressure of the sample are regulated by the high-voltage device to achieve ultrafast pump detection of the sample at different temperatures and pressures.

[0055] According to the low temperature and high pressure ultrafast pump detection system of the third aspect of the present invention, wherein:

[0056] The pump-detection optical components are selected from one or more of the following: semi-transparent and semi-reflective mirrors, delay lines, reflectors, choppers, OPAs, filters, focusing lenses, telephoto microscope objective lenses, light sources, lock-in amplifiers, crystals, relay lenses, and fiber couplers; and / or

[0057] The pump detection imaging component is selected from one or more of the following: a CCD camera, a differential detector, a computer host, and a display screen;

[0058] Preferably, the telephoto microscope objective lens is selected from one or more of the following: a 5x telephoto microscope objective lens, a 10x telephoto microscope objective lens, a 20x telephoto microscope objective lens, a 50x telephoto microscope objective lens, more preferably selected from one or more of the following: a 5x telephoto microscope objective lens, a 10x telephoto microscope objective lens, a 20x telephoto microscope objective lens, and most preferably a 10x telephoto microscope objective lens;

[0059] Preferably, the camera is selected from one or more of the following: a CCD camera, a CMOS camera, a SLR camera, more preferably a CCD camera and / or a CMOS camera, most preferably a CCD camera;

[0060] Preferably, the filter is a 400nm filter and / or an 800nm ​​filter; and / or

[0061] Preferably, the crystal is selected from one or more of the following: BBO crystal, LBO crystal, KDP crystal, preferably BBO crystal or LBO crystal, most preferably BBO crystal.

[0062] A fourth aspect of the present invention provides a temperature control method under high pressure, the temperature control method comprising using the low-temperature double-airbag pressure regulating high-pressure device described in the first aspect;

[0063] Preferably, the temperature control method comprises the following steps: transferring heat through the heat-conducting base and the diamond anvil cell, monitoring the temperature of the heat-conducting base and the temperature of the sample through two temperature sensors, and controlling the temperature of the low-temperature thermostat by controlling the flow rate of the Dewar and the power of the heating coil to control the temperature of the sample under high pressure.

[0064] A fifth aspect of the present invention provides an online in-situ pressure control method at low temperature, the pressure control method comprising using:

[0065] The low-temperature double-airbag pressure regulating high-pressure device described in the first aspect, or

[0066] The online in-situ pressure calibration and imaging system according to the second aspect;

[0067] Preferably, the pressure control method comprises the following steps: filling the first pressurized airbag and the second pressurized airbag with inert gas through the air pressure controller, compressing and stretching the diamond anvil in the diamond anvil pressure chamber to achieve free increase or decrease of the hydrostatic pressure provided to the sample, and measuring the pressure in the diamond anvil in the cryostat through the online in-situ pressure calibration and imaging system to achieve online in-situ pressure control at low temperature.

[0068] A sixth aspect of the present invention provides a pump detection method for ultrafast spectroscopy under low temperature and high pressure, the pump detection method comprising using:

[0069] The low-temperature double-airbag pressure regulating high-pressure device described in the first aspect,

[0070] The online in-situ pressure calibration and imaging system of the second aspect, or

[0071] The low temperature and high pressure ultrafast pump detection system described in the third aspect;

[0072] Preferably, the detection method comprises the following steps: by adjusting the optical path, the pump detection laser emitted by the femtosecond laser is aligned and injected into the telephoto microscope objective lens, and then incident on the sample surface from the optical window of the cold screen in front of the high-pressure device with low-temperature double airbag pressure regulation, so as to realize ultrafast pump detection of samples at different temperatures and pressures;

[0073] More preferably, the detection method further comprises the following steps:

[0074] 1) Loading the sample into the high-voltage device and placing it into the optical path;

[0075] 2) adjusting the sample temperature and pressure, and measuring the calibration pressure by the online in-situ pressure calibration and imaging system; and

[0076] 3) Performing pump detection measurement using the low temperature and high pressure ultrafast pump detection system.

[0077] According to a preferred embodiment of the present invention, the present invention provides a low-temperature double-airbag pressure-regulating high-pressure device, which has a metal shell with an optical window, a metal ring, a gasket, a first pressurized airbag, a second pressurized airbag, a pressurized metal column, a shortened diamond anvil pressure chamber, a first temperature sensor, a second temperature sensor, a cold shield with an optical window, a heating coil, a heat-conducting base, a gas pressure controller, a low-temperature thermostat, a vacuum pump and a liquid nitrogen / liquid helium Dewar; wherein:

[0078] Inside the high-pressure device with low-temperature double airbag pressure regulation, the gasket, pressurized airbag, pressurized metal column, shortened diamond anvil pressure chamber, and first temperature sensor are fixed on the heat-conducting base by the metal ring. The pressurized metal column is located between the pressurized airbag and the diamond anvil pressure chamber. The pressurized airbag is connected to the air pressure controller. The first temperature sensor is located outside the shortened diamond anvil pressure chamber. The cold shield is installed on the heat-conducting base, and the second temperature sensor is installed outside the heat-conducting base. The heating coil is installed at the bottom of the heat-conducting base, and the heat-conducting base is installed in the low-temperature thermostat. The cold shield with optical window and the heat-conducting base are located in the space formed by the metal shell with optical window and the low-temperature thermostat. The vacuum pump and liquid nitrogen / liquid helium dewar are connected to the low-temperature thermostat to provide high vacuum and low-temperature environment for the device.

[0079] Preferably, the diamond of the shortened diamond anvil is selected from one or more of the following: diamond with a platform table diameter of 400 μm, diamond with a platform table diameter of 300 μm, and diamond with a flat table diameter of 200 μm, more preferably selected from one or more of the following: diamond with a platform table diameter of 200 μm, diamond with a flat table diameter of 300 μm, and further selected from one or more of the following: diamond with a flat table diameter of 300 μm.

[0080] According to another preferred embodiment of the present invention, the present invention provides a pressure calibration and imaging system, the system comprising the first aspect of the low-temperature double-airbag pressure regulating high-voltage device, a relay lens, a 20x telephoto microscope objective lens, a 532nm continuous light solid laser, a CCD camera, light, a spectrometer, a semi-transparent and semi-reflective mirror, and a reflector; wherein:

[0081] A sample cavity is provided in the shortened diamond anvil, and the sample is preferably placed beside the ruby ​​in the sample cavity in the shortened diamond anvil;

[0082] The optical path is constructed by using the reflector and the semi-transparent and semi-reflective mirror, and the laser emitted by the 532nm continuous light laser is focused on the ruby ​​in the shortened diamond anvil through the 20x telephoto microscope objective and the relay lens, and the reflected light is guided to the CCD camera and the spectrometer. The CCD can be used to image the sample surface, monitor the sample condition, and observe the sample point irradiated by the laser. The pressure in the diamond anvil is measured by using the displacement of the fluorescence peak of the ruby ​​caused by temperature and pressure.

[0083] According to another preferred embodiment of the present invention, the present invention provides a method for online in-situ pressure control at low temperature, the control method comprising using the low-temperature double-airbag pressure regulating high-pressure device described in the first aspect and the pressure calibration and imaging system described in the second aspect;

[0084] The principle of the test method is as follows: According to the apparatus of the first and second aspects of the present invention, a pressure controller is used to fill a pressurized airbag with high-purity inert gas such as helium or nitrogen to compress and stretch the diamond anvil, thereby freely increasing or decreasing the hydrostatic pressure provided to the sample. The pressure inside the diamond anvil in the cryostat is measured by a pressure calibration and imaging system. Finally, online in-situ pressure control at low temperature is achieved.

[0085] According to another preferred embodiment of the present invention, the present invention provides a method for temperature control under high pressure, the control method comprising using the high-pressure device for low-temperature double-airbag pressure regulation as described in the first aspect;

[0086] Heat is transferred through the heat-conducting base and the diamond anvil cell, the heat-conducting base and the sample temperature are monitored by two temperature sensors, and the sample temperature is regulated by controlling the flow of liquid nitrogen and liquid helium and the power of the heating coil, ultimately achieving temperature regulation under high pressure.

[0087] According to another preferred embodiment of the present invention, the present invention provides an ultrafast spectroscopy experimental method under low temperature and high pressure, the experimental method comprising using the low temperature double airbag pressure regulating high pressure device described in the first aspect and the pressure calibration and imaging system described in the second aspect, and a set of ultrafast pump detection system;

[0088] The temperature and pressure of the sample are regulated by a low-temperature double-airbag pressure-regulating high-pressure device and a pressure calibration and imaging system. By adjusting the optical path, the pump detection laser is aimed and injected into a 10x telephoto microscope objective, and then incident on the sample surface from the optical window in front of the low-temperature airbag pressure-regulating high-pressure device, thereby realizing ultrafast pump detection of samples at different temperatures and pressures.

[0089] Compared with the prior art, the low temperature and high pressure ultrafast pump detection system of the present invention has the following settings:

[0090] (1) Add a diamond anvil cell to the cryostat.

[0091] (2) Adding (double) air film driven online in-situ high pressure pressure regulation in the cryostat.

[0092] (3) A shortened diamond anvil high pressure press chamber suitable for cryostat.

[0093] (4) Install a heat-conducting base in the low-temperature thermostat to control and monitor the temperature of the diamond anvil for heating and cooling.

[0094] (5) An online in-situ time-resolved ultrafast pump-probe system is placed outside the cryostat.

[0095] (6) An online in-situ high pressure calibration and imaging system is placed outside the cryostat.

[0096] (7) An online in-situ relay lens confocal imaging monitoring system is placed outside the cryostat.

[0097] The low-temperature and high-pressure ultrafast pump detection system of the present invention is used as an ultrafast pump detection test experimental system to study the ultrafast dynamic characteristics of materials under low temperature and high pressure.

[0098] As a low-temperature spectral measurement system, it is used for various spectral tests at low temperatures, as well as for various instrument processing or material growth at low temperatures.

[0099] As a high-voltage system, it is used for various spectrum testing methods and device designs that require free increase or decrease of voltage regulation.

[0100] The low-temperature and high-pressure ultrafast pump-probe system of the present invention realizes online in-situ ultrafast spectroscopy experiments and can perform pump-probe ultrafast spectroscopy measurements on samples at 6-325K and 0-80GPa.

[0101] Compared with the prior art, the online in-situ low-temperature and high-pressure ultrafast spectroscopy device, its system and method of the present invention can have but are not limited to the following beneficial effects:

[0102] (1) Temperature control of 6-325K under high pressure with dual airbag pressure regulation is achieved.

[0103] (2) The free pressure increase and decrease control at low temperature is realized online and in situ, and the pressure can be continuously adjusted within the range of 0-80 GPa with an accuracy of 0.1 GPa.

[0104] (3) Online in-situ low-temperature and high-pressure ultrafast spectroscopy and ultrafast dynamics measurements were achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0105] The embodiments of the present invention are described in detail below with reference to the accompanying drawings, wherein:

[0106] Figure 1 The structural diagram of the high-pressure device for low-temperature double-airbag pressure regulation in Example 1 is shown.

[0107] Figure 2 The structural diagram of the online in-situ pressure calibration and imaging system in Example 2 is shown.

[0108] Figure 3 The structure diagram of the low-temperature and high-pressure ultrafast pump detection system in Example 3 is shown.

[0109] Figure 4 The structural diagram of the low-temperature and high-pressure ultrafast pump detection system in Example 4 is shown.

[0110] Figure 5 The results of the sample under test in the CCD camera at different temperatures and pressures are shown; Figure 5 A shows the results of the layered iron-based superconducting sample to be tested at 78K and 25.552GPa; Figure 5 B shows the results of the layered iron-based superconducting sample under test at 300K and 2.27GPa.

[0111] Figure 6 The ruby ​​photoluminescence spectrum at a temperature of 13.25 K is shown. By comparing the shift of the peak position of the photoluminescence spectrum at room temperature and pressure, it is found that the pressure at this time is 20.81 GPa.

[0112] Figure 7 Shown are the pump-probe data of ultrafast spectroscopy of layered iron-based superconducting samples at a pressure of 13.7 GPa, 8.5 K and 20 K.

[0113] Description of reference numerals:

[0114] 2. Cold shield with optical window; 1. Metal shell with another optical window; 3. First metal ring, first gasket and first pressurized airbag; 4. Pressurized metal column; 5. Diamond anvil pressure chamber; 6. First temperature sensor; 7. Sample and ruby; 8. Second metal ring, second gasket and second pressurized airbag; 9. Second temperature sensor; 10. Heating coil; 11. Heat-conducting base; 12. Low-temperature thermostat; 13. Vacuum pump; 14. Dewar; 15. Air pressure controller; 16. High-pressure device for low-temperature double airbag pressure regulation; 17. Relay lens; 18. 20x telephoto microscope objective lens; 19. First semi-transparent and semi-reflective mirror; 20. Second semi-transparent and semi-reflective mirror; 21. Fiber optic coupler; 22. Spectrum analyzer; 23. First CCD camera; 24. Computer host; 25 , the third semi-transparent and semi-reflective mirror; 26, the first reflector; 27, the light source; 28, the 532nm continuous light laser; 29, the femtosecond laser; 30, the fourth semi-transparent and semi-reflective mirror; 31, the delay line; 32, the second reflector; 33, the third reflector; 34, the chopper; 35, the OPA; 36, the 400nm filter; 37, the fourth reflector; 38, the fifth semi-transparent and semi-reflective mirror; 39, the sixth semi-transparent and semi-reflective mirror; 40, the seventh semi-transparent and semi-reflective mirror; 41, the fifth reflector; 42, the 800nm ​​filter; 43, the first focusing lens; 44, the differential detector; 45, the second focusing lens; 46, the second CCD camera; 47, the 10x telephoto microscope objective; 48, the phase-locked amplifier; 49, the third focusing lens; 50, the BBO crystal; 51, the fourth focusing lens. DETAILED DESCRIPTION

[0115] The present invention will be further described below through specific embodiments in conjunction with the accompanying drawings. However, it should be understood that these embodiments are only used for more detailed and specific description and should not be understood as limiting the present invention in any form.

[0116] This section generally describes the materials and test methods used in the experiments of the present invention. Although many materials and operating methods used to achieve the purpose of the present invention are well known in the art, the present invention is still described as detailed as possible. It is clear to those skilled in the art that in the context, if not specifically stated, the materials and operating methods used in the present invention are well known in the art.

[0117] Example 1

[0118] This embodiment is an exemplary description of the low-temperature double-airbag pressure regulating high-pressure device of the present invention.

[0119] like Figure 1As shown, the low-temperature double-airbag pressure regulating high-pressure device of the present invention comprises: a cold shield 2 with an optical window; a metal shell 1 with another optical window; a first metal ring, a first gasket and a first pressurized airbag 3; a pressurized metal column 4; a diamond anvil pressure chamber 5; a first temperature sensor 6; a sample and a ruby ​​7; a second metal ring, a second gasket and a second pressurized airbag 8; a second temperature sensor 9; a heating coil 10; a heat-conducting base 11; a low-temperature thermostat 12; a vacuum pump 13; a dewar 14; and a gas pressure controller 15.

[0120] The diamond anvil cell of this embodiment takes a shortened diamond anvil cell as an example.

[0121] Inside the high-pressure device with low-temperature double airbag pressure regulation, the first gasket, the second gasket, the first pressurized airbag, the second pressurized airbag, the pressurized metal column, the shortened diamond anvil pressure chamber, and the first temperature sensor are fixed in the thermally conductive base by the first metal ring and the second metal ring. The pressurized metal column is located between the first pressurized airbag and the diamond anvil pressure chamber. The first pressurized airbag and the second pressurized airbag are connected to the air pressure controller. The first temperature sensor is located outside the shortened diamond anvil pressure chamber. The cold shield is installed on the thermally conductive base, and the second temperature sensor is installed outside the thermally conductive base. The thermally conductive base and the cold shield are fixed in the low-temperature thermostat. The cold shield with an optical window and the thermally conductive base are located in the space formed by the metal shell with an optical window and the low-temperature thermostat. The vacuum pump and the liquid nitrogen / liquid helium dewar are connected to the low-temperature thermostat to provide a high vacuum and low-temperature environment for the device. This embodiment takes the liquid helium dewar as an example.

[0122] Example 2

[0123] This embodiment is an exemplary description of the online in-situ pressure calibration and imaging system of the present invention.

[0124] like Figure 2 As shown, the pressure calibration and imaging system of the present invention comprises: the low-temperature double-airbag pressure-adjusting high-pressure device 16 described in Example 1, a 532nm continuous light laser 28, an online in-situ pressure calibration optical component, and an online in-situ sample appearance imaging component. The 532nm continuous light laser emits a 532nm laser, which is focused on the ruby ​​of the high-pressure device through the optical path constructed by the online in-situ pressure calibration optical component, and the optical path guides the reflected light to the online in-situ sample appearance imaging component to realize the detection and calibration of the pressure values ​​in the diamond anvil under different temperatures and pressures.

[0125] The online in-situ pressure calibration optical components of this embodiment are exemplified by semi-transparent and semi-reflective mirrors, reflectors, light sources, relay lenses, telephoto microscopes, and fiber couplers. The online in-situ sample appearance imaging components are exemplified by CCD cameras, spectrometers, and computer hosts. The telephoto microscope is exemplified by a 20x telephoto microscope, and the CCD camera is exemplified by a 3672 color CCD camera with a resolution of 5496x.

[0126] The ruby ​​is placed in the high-voltage device, and the 532nm continuous light laser emits a 532nm laser, which is focused on the ruby ​​through the optical path constructed by the optical component. The optical path guides the reflected light to the online in-situ sample morphology imaging component to realize the detection and calibration of the pressure values ​​in the diamond anvil at different temperatures and pressures.

[0127] This embodiment uses Figure 2 Taking the optical path of as an example, the 532nm laser 28 emits laser light, which is reflected by the third semi-transparent and semi-reflective mirror 25; the light source 27 provides white light, which passes through the first reflector 26, and then through the third semi-transparent and semi-reflective mirror 25, through the first semi-transparent and semi-reflective mirror 19, through the 20x telephoto microscope objective lens 18 and the relay lens 17 to focus on the sample to be tested and the ruby ​​7, and guide the reflected light to the first CCD camera 23 and the spectrometer 22. The first CCD camera 23 can be used to image the sample surface, monitor the sample status and observe the sample point irradiated by the laser, and the spectrometer 22 is used to analyze the ruby ​​fluorescence peak. The light source 27 is located in the optical path to provide a light source for the CCD camera to monitor the sample surface, and the laser is used to provide laser light to irradiate the ruby. The spectrometer is used to analyze the displacement of the ruby ​​fluorescence peak at different pressures and temperatures, and finally the pressure detection is realized.

[0128] Example 3

[0129] This embodiment is an exemplary description of the low-temperature and high-pressure ultrafast pump detection system of the present invention.

[0130] The low-temperature, high-pressure, ultrafast pump detection system of the present invention comprises: the pressure calibration and imaging system described in Example 2, a femtosecond laser 29, a pump detection optical component, and a pump detection imaging component. The sample to be tested is placed in the high-pressure device, the femtosecond laser emits a femtosecond laser, and the optical path constructed by the pump detection optical component is divided into two beams of light and focused into the high-pressure device. The optical path guides the reflected light to the pump detection imaging component. The temperature and pressure of the sample to be tested are regulated by the high-pressure device and the pressure chamber calibration system to achieve ultrafast pump detection of samples at different temperatures and pressures.

[0131] The pump detection optical components described in this embodiment are exemplified by semi-transparent and semi-reflective mirrors, delay lines, reflectors, choppers, OPAs, filters, focusing lenses, telephoto microscopes, light sources, and lock-in amplifiers. The pump detection imaging components are exemplified by CCD cameras, differential detectors, and computer hosts. The telephoto microscopes are exemplified by 10x telephoto microscopes, and the cameras are exemplified by color CCD cameras with a resolution of 5496×3672.

[0132] This embodiment uses Figure 3 Taking the optical path of as an example, the femtosecond laser emits a femtosecond laser, which is divided into two optical paths through the fourth semi-transparent and semi-reflective mirror 30, one of which passes through the delay line 31 and is focused on the surface of the sample to be tested through the 10x telephoto microscope objective lens 47, and the other optical path passes through the third reflector 33, the chopper 34, the OPA 35, the 400nm filter 36, the fourth reflector 37 and then through the 10x telephoto microscope objective lens 47 to focus on the same point of the sample to be tested. The reflected light enters the differential detector 44 through the optical path. The light source irradiates the surface of the sample to be tested through the optical path, and the reflected light enters the second CCD camera 46 through the optical path. The pressure calibration and imaging system optical path is placed on the right side of the high-pressure device.

[0133] Example 4

[0134] This embodiment is another exemplary description of the cryogenic and high-pressure ultrafast pump detection system of the present invention. The cryogenic and high-pressure ultrafast pump detection system of the present invention comprises: the pressure calibration and imaging system described in Example 2, a femtosecond laser 29, a pump detection optical component, and a pump detection imaging component. The difference from Example 3 is the difference in the optical path composed of the pump detection optical component, and the rest is the same as Example 3.

[0135] The pump detection optical components described in this embodiment are exemplified by semi-transparent and semi-reflective mirrors, delay lines, reflectors, choppers, lenses, BBO crystals, filters, focusing lenses, telephoto microscopes, light sources, and lock-in amplifiers. The pump detection imaging components are exemplified by CCD cameras, differential detectors, and computer hosts. The telephoto microscopes are exemplified by 10x telephoto microscopes, and the cameras are exemplified by color CCD cameras with a resolution of 5496×3672.

[0136] This embodiment uses Figure 4Taking the optical path of as an example, the femtosecond laser emits a femtosecond laser, which is divided into two optical paths through the fourth semi-transparent and semi-reflective mirror 30, one of which passes through the delay line 31 and is focused on the surface of the sample to be tested through the 10x telephoto microscope objective lens 47, and the other optical path passes through the chopper 34, the third focusing lens 49, the BBO crystal 50, the fourth focusing lens 51, the 400nm filter 36, the fourth reflector 37 and then focuses on the same point of the sample to be tested through the telephoto microscope objective lens 47. The reflected light enters the differential detector 44 through the optical path. The light source irradiates the surface of the sample to be tested through the optical path, and the reflected light enters the second CCD camera 46 through the optical path. The pressure calibration and imaging system optical path is placed on the right side of the high-voltage device.

[0137] Example 5

[0138] This embodiment is used to illustrate the method of temperature control under high pressure of the low-temperature double-airbag pressure regulating high-pressure device of the present invention.

[0139] According to the high-pressure device with low-temperature double-airbag pressure regulation of Example 1, heat is transferred through the heat-conducting base and the diamond anvil pressure chamber, the temperature of the heat-conducting base and the sample to be tested is monitored by two temperature sensors, and the temperature of the sample to be tested is regulated by controlling the flow of liquid nitrogen and liquid helium and the power of the heating coil, thereby finally achieving temperature regulation under high pressure.

[0140] Example 6

[0141] This embodiment is used to illustrate the method for online in-situ pressure control at low temperature of the online in-situ pressure calibration and imaging system of the present invention.

[0142] According to the online in-situ pressure calibration and imaging system of Example 2, the pressure controller is used to fill the pressurized airbag with high-purity inert gas helium to compress and stretch the diamond anvil, thereby freely increasing or decreasing the hydrostatic pressure provided to the sample to be tested. The pressure inside the diamond anvil in the cryostat is measured by the pressure calibration and online in-situ sample appearance imaging components. Finally, online in-situ pressure control at low temperature is achieved.

[0143] Combining Examples 5 and 6, Figure 5 The results of the sample under test in the CCD camera at different temperatures and pressures are shown; Figure 5 A shows the image of the layered iron-based superconducting sample to be tested at 25.552 GPa; Figure 5 B shows the image of the layered iron-based superconducting sample to be tested at 2.27 GPa.

[0144] Figure 6The ruby ​​photoluminescence spectrum at a temperature of 13.25 K is shown. By comparing the shift of the peak position of the photoluminescence spectrum at room temperature and pressure, it is found that the pressure at this time is 20.81 GPa.

[0145] Example 7

[0146] This embodiment is used to illustrate the low-temperature online in-situ pump detection measurement of the low-temperature and high-pressure ultrafast pump detection system of the present invention.

[0147] According to the low-temperature, high-pressure, ultrafast pump detection system of Examples 3 and 4, the temperature and pressure of the sample are regulated by a low-temperature double-airbag pressure-regulating high-pressure device and a pressure calibration and imaging system. By adjusting the optical path, the pump detection laser is aligned and injected into a 10x telephoto microscope objective lens, and then incident on the sample surface from the optical window of the cold screen in front of the low-temperature airbag pressure-regulating high-pressure device, thereby realizing ultrafast pump detection of samples at different temperatures and pressures.

[0148] In this embodiment, a layered iron-based superconducting sample is taken as an example. First, the vacuum pump is turned on at 300K to make the sample chamber a high vacuum environment for 10 -5 Pa, vacuum degree reaches 10 -5 Pa, the sample chamber temperature was lowered, and after reaching the test temperature of 20K, it was kept constant at 20K. The pressure of the sample chamber was adjusted to 13.7GPa by the air pressure controller. The pump detection test of the sample was carried out. The same steps were used to carry out the pump detection test of the sample at 8.5K and 13.7GPa.

[0149] Figure 7 Shown are the pump-probe data of ultrafast spectroscopy of layered iron-based superconducting samples at a pressure of 13.7 GPa, 8.5 K and 20 K.

[0150] Comparative Example

[0151] This comparative example is used to compare the prior art and the low-temperature double-airbag pressure regulating high-pressure device, the online in-situ pressure calibration and imaging system, and the low-temperature high-pressure ultrafast pump detection system of the present invention.

[0152] Comparative Example 1: It consists of a single-airbag high-pressure device, a pressure calibration and imaging system, and an ultrafast pump detection system.

[0153] Comparative Example 2: It consists of a single airbag high-pressure sample chamber and a spectrometer.

[0154] Comparative Example 3: includes: a laser, a Brillouin optical path system, a vacuum high-pressure sample containing system, a signal acquisition and processing system, a vacuum high-pressure sample containing system and a cooling system.

[0155] Comparative Example 4: includes: a laser light source, an objective lens collection system, and a Raman spectrometer; the main structures of the Raman spectrometer include a slit, a monochromator, a grating, and a charge-coupled device, there is a laser switching system between the objective lens collection system and the Raman spectrometer, and there is a high-voltage system at the end of the objective lens collection system.

[0156] As shown in Table 1, compared with the prior art, the low-temperature dual-airbag pressure-regulating high-pressure device and the low-temperature and high-pressure ultrafast pump detection system of the present invention can realize online in-situ calibration pressure at low temperature, realize free increase and decrease of dual-airbag pressure regulation at low temperature, and realize temperature control at high pressure, and the device can be used for ultra-pump detection measurement.

[0157] Table 1 Comparison of the prior art and the present invention's low-temperature double-airbag pressure regulating high-pressure device, online in-situ pressure calibration and imaging system, and low-temperature high-pressure ultrafast pump detection system

[0158]

[0159] Although the effects of some embodiments are shown above, those skilled in the art should understand that according to the concept of the present invention, the aforementioned other embodiments without specific effects or other technical solutions of the present invention not shown in the embodiments can also achieve the following technical effects stated in the invention content section that are equivalent to the embodiments:

[0160] (1) Temperature control of 6-325K under high pressure with dual airbag pressure regulation is achieved.

[0161] (2) The free pressure increase and decrease control at low temperature is realized online and in situ, and the pressure can be continuously adjusted within the range of 0-80 GPa with an accuracy of 0.1 GPa.

[0162] (3) Online in-situ low-temperature and high-pressure ultrafast spectroscopy and ultrafast dynamics measurements were achieved.

[0163] Although the present invention has been described to a certain extent, it is obvious that appropriate changes in various conditions can be made without departing from the spirit and scope of the present invention. It is understood that the present invention is not limited to the embodiments described, but belongs to the scope of the claims, which includes equivalent replacements of each factor described.

Claims

1. A low-temperature double-airbag pressure regulating high-pressure device, characterized in that: The high-pressure device comprises: a cold shield with an optical window, a metal ring, a gasket, a first pressurized airbag, a second pressurized airbag, a pressurized metal column, a diamond anvil pressure chamber, a first temperature sensor, a second temperature sensor, a thermally conductive base, a cryostat and a gas pressure controller; wherein: The metal ring fixes the gasket, the first pressurized airbag, the second pressurized airbag, the pressurized metal column, the diamond anvil pressure chamber and the first temperature sensor on one side of the thermally conductive base; The second temperature sensor is independent of the metal ring and is disposed on the other side of the heat-conducting base; The thermally conductive base and the cold shield are fixed on the cryostat.

2. The high voltage device according to claim 1, characterized in that: The high-voltage device further comprises a heating coil, and the heating coil is arranged on the same side of the heat-conducting base as the second temperature sensor; wherein, The first temperature sensor is located outside the diamond anvil cell; The pressurized metal column is located between the gasket and the diamond anvil pressure chamber; The first pressurized airbag and the second pressurized airbag are both connected to the air pressure controller; The metal ring comprises a first metal ring and a second metal ring, wherein the first metal ring and the first gasket are preferably connected to the first pressurized airbag; and / or The gasket includes a first gasket and a second gasket, and the second metal ring and the second gasket are preferably connected to the second pressurized airbag.

3. The high voltage device according to claim 1 or 2, characterized in that: The high-pressure device further comprises: a metal housing having another optical window, a vacuum pump for providing a vacuum environment, and a Dewar for providing a low-temperature environment; wherein, The cold shield and the thermally conductive base are located in a space formed by the metal housing and the cryostat; and / or The vacuum pump and the Dewar are connected to the cryostat; Preferably, the low temperature environment of the high pressure device is 6 to 325K, more preferably 20 to 315K, and further preferably 40 to 300K; Preferably, the high pressure of the high pressure device is 0 to 80 GPa, more preferably 5 to 70 GPa, and further preferably 10 to 60 GPa; Preferably, the diamond anvil in the diamond anvil pressure chamber is a shortened diamond anvil; and / or Preferably, the Dewar is selected from one or more of the following: a cryogenic liquid nitrogen tank, a liquid nitrogen Dewar, a liquid helium Dewar, more preferably a liquid nitrogen Dewar or a liquid helium Dewar, most preferably a liquid helium Dewar.

4. An online in-situ pressure calibration and imaging system, characterized in that: The online in-situ pressure calibration and imaging system comprises: The low-temperature double-airbag pressure regulating high-pressure device according to any one of claims 1 to 3; CW laser; Online in-situ calibration of optical components; and Online in-situ sample appearance imaging component; Among them, the continuous light laser emits laser, which is focused on the ruby ​​of the high-voltage device through the optical path constructed by the online in-situ pressure calibration optical component. The optical path guides the reflected light to the online in-situ sample morphology imaging component to realize the detection and calibration of the pressure values ​​in the diamond anvil under different temperatures and pressures.

5. The online in-situ pressure calibration and imaging system according to claim 4, characterized in that: The wavelength of the continuous laser is selected from one or more of the following: 532nm, 633nm, 450nm, preferably 532nm or 633nm, most preferably 532nm; The online in-situ pressure correction optical components are selected from one or more of the following: a semi-transparent and semi-reflective mirror, a reflector, a light source, a relay lens, a fiber coupler, and a telephoto microscope objective lens; and / or The online in-situ sample appearance imaging component is selected from one or more of the following: a spectrometer, a camera, and a computer host; Preferably, the telephoto microscope objective lens is selected from one or more of the following: a 5x telephoto microscope objective lens, a 10x telephoto microscope objective lens, a 20x telephoto microscope objective lens, a 50x telephoto microscope objective lens, more preferably a 10x telephoto microscope objective lens or a 20x telephoto microscope objective lens, most preferably a 20x telephoto microscope objective lens; and / or Preferably, the camera is selected from one or more of the following: a CCD camera, a CMOS camera, a SLR camera, more preferably a CCD camera and / or a CMOS camera, most preferably a CCD camera.

6. A low temperature and high pressure ultrafast pump detection system, characterized in that: The low temperature and high pressure ultrafast pump detection system comprises: The online in-situ pressure calibration and imaging system according to claim 4 or 5; Femtosecond lasers; pump-probe optics; and Pump-probe imaging components; Among them, the femtosecond laser emits a femtosecond laser, which is divided into two beams of light through the optical path constructed by the pump-detection optical component, and is focused together into the low-temperature double-airbag pressure-regulating high-voltage device. The optical path guides the reflected light to the pump-detection imaging component, and the temperature and pressure of the sample are regulated by the high-voltage device to achieve ultrafast pump detection of the sample at different temperatures and pressures.

7. The low temperature, high pressure, ultrafast pump detection system according to claim 6, characterized in that: The pump-detection optical components are selected from one or more of the following: semi-transparent and semi-reflective mirrors, delay lines, reflectors, choppers, OPAs, filters, focusing lenses, telephoto microscope objective lenses, light sources, lock-in amplifiers, crystals, relay lenses, and fiber couplers; and / or The pump detection imaging component is selected from one or more of the following: a CCD camera, a differential detector, a computer host, and a display screen; Preferably, the telephoto microscope objective lens is selected from one or more of the following: a 5x telephoto microscope objective lens, a 10x telephoto microscope objective lens, a 20x telephoto microscope objective lens, a 50x telephoto microscope objective lens, more preferably selected from one or more of the following: a 5x telephoto microscope objective lens, a 10x telephoto microscope objective lens, a 20x telephoto microscope objective lens, and most preferably a 10x telephoto microscope objective lens; Preferably, the camera is selected from one or more of the following: a CCD camera, a CMOS camera, a SLR camera, more preferably a CCD camera and / or a CMOS camera, most preferably a CCD camera; Preferably, the filter is a 400nm filter and / or an 800nm ​​filter; and / or Preferably, the crystal is selected from one or more of the following: BBO crystal, LBO crystal, KDP crystal, preferably BBO crystal or LBO crystal, most preferably BBO crystal.

8. A temperature control method under high pressure, characterized in that: The temperature control method comprises using a low-temperature double-airbag pressure regulating high-pressure device as described in any one of claims 1 to 3; Preferably, the temperature control method comprises the following steps: transferring heat through the heat-conducting base and the diamond anvil cell, monitoring the temperature of the heat-conducting base and the temperature of the sample through two temperature sensors, and controlling the temperature of the low-temperature thermostat by controlling the flow rate of the Dewar and the power of the heating coil to control the temperature of the sample under high pressure.

9. A method for online in-situ pressure control at low temperature, characterized in that: The pressure control method comprises using: The low-temperature double-airbag pressure regulating high-pressure device according to any one of claims 1 to 3, or The online in-situ pressure calibration and imaging system according to claim 4 or 5; Preferably, the pressure control method comprises the following steps: filling the first pressurized airbag and the second pressurized airbag with inert gas through the air pressure controller, compressing and stretching the diamond anvil in the diamond anvil pressure chamber to achieve free increase or decrease of the hydrostatic pressure provided to the sample, and measuring the pressure in the diamond anvil in the cryostat through the online in-situ pressure calibration and imaging system to achieve online in-situ pressure control at low temperature.

10. A pump detection method for ultrafast spectroscopy under low temperature and high pressure, characterized in that: The pump-probe method comprises using: The low-temperature double-airbag pressure regulating high-pressure device according to any one of claims 1 to 3, The online in-situ pressure calibration and imaging system according to claim 4 or 5, or The low temperature and high pressure ultrafast pump detection system according to claim 6 or 7; Preferably, the detection method comprises the following steps: by adjusting the optical path, the pump detection laser emitted by the femtosecond laser is aligned and injected into the telephoto microscope objective lens, and then incident on the sample surface from the optical window of the cold screen in front of the high-pressure device with low-temperature double airbag pressure regulation, so as to realize ultrafast pump detection of samples at different temperatures and pressures; More preferably, the detection method further comprises the following steps: 1) Loading the sample into the high-voltage device and placing it into the optical path; 2) adjusting the sample temperature and pressure, and measuring the calibration pressure by the online in-situ pressure calibration and imaging system; and 3) Performing pump detection measurement using the low temperature and high pressure ultrafast pump detection system.

Images