Diamond anvil cell corner high-pressure device for low-temperature high-intensity magnetic field electrical test

Abstract

The invention discloses a diamond anvil cell corner high-pressure device for low-temperature high-intensity magnetic field electrical test, which comprises a press rotating table arranged in a low-temperature superconducting magnet sample cavity and a stepping motor arranged at room temperature, the stepping motor is connected with a motor controller through a motor communication cable, the motor controller is connected with a computer through a USB cable, and the computer is connected with the press rotating table. The press rotating table is connected with a stepping motor through a transmission shaft; the press rotating table is provided with a quick plug-in adapter, the diamond anvil cell press is arranged on the quick plug-in adapter, and a test sample is placed in the diamond anvil cell press; the diamond anvil cell press can be dismounted from and mounted on the rotating shaft by the quick plug-pull adapter in a plug-pull manner, and room-temperature pressure calibration and low-temperature electrical test can be completed without changing electrical wiring. According to the invention, the electrical test of the material is realized in a limited space in a low-temperature strong magnetic field environment.

Description

Technical Field

[0001] The present invention relates to the technical field of material electrical performance testing, and in particular to a diamond anvil angle high-voltage device for low-temperature, high-magnetic-field electrical testing. Background Art

[0002] Comprehensive extreme measurement technology under high pressure, low temperature, and strong magnetic fields has greatly promoted the discovery and research of new states of matter, new physical phenomena, and physical laws in materials. Developing experimental methods for multi-physics field coupling control under extreme conditions such as ultra-high pressure, ultra-low temperature, and strong magnetic fields, and exploring the application of these extreme conditions in materials, including the discovery of novel quantum states, the understanding of unconventional superconducting mechanisms, and the characterization of quantum phase transitions, not only has important academic value in basic research, but also can lay a solid foundation for future technological development and progress. The presses used in existing high-pressure technologies are too heavy and the sample space is small. By regulating the shape and symmetry of the Fermi surface in the band structure through high-pressure technology, pressure-induced superconductivity can be achieved. However, how to achieve dimensional control of high-pressure superconductivity, that is, how to realize a diamond anvil high-pressure rotation device in a confined space under a low-temperature and strong magnetic field environment and realize electrical testing of materials, remains a challenge. Summary of the Invention

[0003] Purpose of the invention: The purpose of the present invention is to provide a diamond anvil angle high-voltage device for electrical testing at low temperature and strong magnetic field. It adopts a miniaturized and lightweight diamond anvil non-magnetic press design, which can reduce the size of the press, reduce the weight of the press, and balance the center of gravity of the press; and combined with a quick-plug adapter, it not only realizes the electrical measurement of the angle under low temperature and strong magnetic field, but also realizes simple and quick plug-in electrical contact in the form of conductive pins and sockets.

[0004] Technical solution: A diamond anvil angle high-voltage device for low-temperature, high-magnetic-field electrical testing, comprising a press rotary table placed in a low-temperature superconducting magnet sample cavity, a stepper motor placed at room temperature, the stepper motor connected to a motor controller via a motor communication cable, the motor controller connected to a computer via a USB cable, the press rotary table mechanically connected to the stepper motor via a transmission shaft; a quick-swap adapter is installed on the press rotary table, the diamond anvil press is arranged on the quick-swap adapter, the quick-swap adapter includes a pin end and a socket base end, and the test sample is placed on the press rotary table. Inside the diamond anvil press; a test sample placed on the upper diamond anvil surface is connected to the annular PCB circuit board through an external platinum wire, and then connected to the first electrode terminal block on the adapter PCB circuit board through an enameled copper wire. The first electrode terminal block is conductively connected to the second electrode terminal block on the pin PCB circuit board. The second electrode terminal block is connected to the conductive pin on the pin end through the enameled copper wire. The conductive pin is electrically conductively connected to the conductive socket on the socket base end in a plug-in manner. The conductive socket is externally connected to an external measuring meter through a signal line on the rotating sample rod, ultimately realizing the measurement of the electrical characteristics of the test sample.

[0005] Furthermore, the diamond anvil cell press comprises:

[0006] A pair of upper and lower diamond anvil cells with the same table diameter;

[0007] An upper anvil block and a lower anvil block for fixing the upper and lower diamond anvils;

[0008] A boss slider that fixes the upper anvil pad;

[0009] A lower pad base for fixing the lower anvil pad;

[0010] A slider guide cylinder for limiting the lateral movement of the boss slider;

[0011] A left-hand pressure screw and a right-hand pressure screw for adjusting the distance between the upper and lower diamond anvils;

[0012] A ring-shaped PCB circuit board fixed to the boss slider for electrical test leads.

[0013] Furthermore, the material of the diamond anvil cell press is non-magnetic beryllium copper, and the pressure range that can be generated is 0 to 150 GPa.

[0014] Furthermore, the diamond anvil press is assembled on the pin end, and the pin end and the socket base end can be separated;

[0015] The upper end surface of the pin end is equipped with a transfer PCB circuit board for electrical conduction, and the lower end surface is equipped with a pin PCB circuit board for electrical conduction, and the pin PCB circuit board is welded with conductive pins;

[0016] The lower end surface of the jack base end is installed with a jack PCB circuit board for electrical conduction, and a conductive jack is welded on the jack PCB circuit board; a press rotating bearing hole is opened on the side of the jack base end, and the press rotating bearing hole is a through hole.

[0017] Furthermore, the pin end and the jack base end are made of brass.

[0018] Furthermore, the adapter PCB circuit board is provided with a first electrode terminal block for electrically connecting to the wires drawn from the sample in the press; and a second electrode terminal block is also provided for electrically connecting to the conductive pins on the pin PCB circuit board;

[0019] The surface of the conductive pin is gold-plated;

[0020] The adapter PCB and the pin PCB are connected by soldering using enameled copper wire;

[0021] The surface of the conductive socket is gold-plated, and a retaining spring is provided in the hole;

[0022] The conductive pins and conductive sockets are the same in number, position and size, and matched to ensure electrical connection or disconnection.

[0023] Compared with the prior art, the present invention has the following significant effects:

[0024] 1. When the electrical wiring is completed, the present invention can realize the rapid removal and installation of the diamond anvil press from the rotating rod through the quick plug-in adapter. Without repeated electrical wiring, multiple room temperature pressurization, pressure calibration and low-temperature electrical tests can be completed alternately, which greatly reduces the electrical impact of repeated electrode wiring on the sample and reduces the probability of damage to the test sample.

[0025] 2. The diamond anvil cell press of the present invention adopts a variety of uniquely designed PCB circuit boards, making the electrical wiring of the sample simpler and more convenient;

[0026] 3. The present invention realizes the rotation of the diamond anvil press in extreme environments through remote program control, which is easy to operate;

[0027] 4. The present invention is suitable for high-precision electrical testing of rotation angles under comprehensive extreme conditions of ultra-high pressure, extremely low temperature, and strong magnetic field. During the pressure calibration process, there is no need to repeatedly disconnect / connect the electrical connection between the sample and the sample rod, thus avoiding unnecessary external impact on the sample. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 An overall system diagram of a rotary diamond anvil cell high-pressure device provided in an embodiment of the present invention;

[0029] Figure 2 A schematic diagram of a rotated diamond anvil cell high-pressure device provided in an embodiment of the present invention;

[0030] Figure 3 An exploded view of the base end and pin end of the quick-plug adapter provided by an embodiment of the present invention;

[0031] Figure 4 A cross-sectional view of a boss slider provided by an embodiment of the present invention;

[0032] Figure 5 A cross-sectional view of a rotated diamond anvil cell high-pressure device provided by an embodiment of the present invention;

[0033] Figure 6 A diagram showing the rotation angle accuracy of the rotated diamond anvil cell high-voltage device provided by an embodiment of the present invention, as verified by a magnetic field angle-dependent resistance test of a typical superconducting sample;

[0034] Figure: 1. Press rotary table; 2. Stepper motor; 3. Motor controller; 4. Computer; 5. Motor communication cable; 6. USB cable; 7. Drive shaft; 8. Diamond anvil press; 9. Boss slider; 10. Slider guide cylinder; 11. Lower pad base; 12. Upper anvil pad; 13. Lower anvil pad; 14. Upper diamond anvil; 15. Lower diamond anvil; 16. Limiting screw; 17. Left-handed pressure screw; 18. Right-handed pressure screw; 19. Lower pad base fixing screw; 20. Upper pad fixing short screw; 21. Lower pad fixing long screw; 22 , annular PCB circuit board; 23, annular PCB circuit board fixing screws; 24, pin end; 25, adapter PCB circuit board; 26, pin PCB circuit board; 27, first PCB circuit board fixing screws; 28, second PCB circuit board fixing screws; 29, press machine fixing screws; 30, conductive pin; 31, jack base end; 32, jack PCB circuit board; 33, third PCB circuit board fixing screws; 34, conductive jack; 35, press machine rotating bearing hole; 36, adapter pin end and jack end fixing screws; 37, second electrode terminal block, 38, first electrode terminal block. DETAILED DESCRIPTION

[0035] The present invention will be described in further detail below with reference to the accompanying drawings and specific implementations.

[0036] like Figure 1As shown, this is an overall system diagram of the angled diamond anvil high-pressure device for low-temperature and strong magnetic field electrical testing of the present invention, including a press rotary table 1 placed in a low-temperature superconducting magnet sample cavity, a stepper motor 2 for controlling the angle of rotation located at room temperature, the stepper motor 2 connected to the press rotary table 1 via a transmission shaft 7, the stepper motor 2 connected to the motor controller 3 via a motor communication cable 5, the motor controller 3 connected to the computer 4 via a USB cable 6, and finally the rotation of the press rotary table 1 is realized by the control software on the computer 4.

[0037] like Figure 2 As shown, the diamond anvil press 8 of the present invention is assembled on the pin end 24 of the quick-plug adapter, and is tightened and fixed by using the press fixing screw 29 from the side threaded hole of the pin end 24, and the upper end surface of the slider guide cylinder 10 is kept flush with the upper surface of the adapter PCB circuit board 25 to ensure that the center of gravity of the diamond anvil press 8 is on the press rotation axis, and the socket base end 31 of the quick-plug adapter is fixed to the press rotary table 1 using a bearing through the press rotation bearing hole 35. The range of rotation of the diamond anvil press 8 around the rotary press bearing hole 35 is limited to a spherical space with a diameter not exceeding 48 mm, the rotation angle range is -5° to 365°, and the angular resolution is better than 0.01°.

[0038] like Figure 3 As shown, the diamond anvil press 8 of the present invention is assembled on the pin end 24 of the quick-disconnect adapter, but is separated from the socket base end 31 of the quick-disconnect adapter.

[0039] like Figure 4 FIG. 1 is a cross-sectional view of the boss slider 9 of the diamond anvil press according to the present invention.

[0040] like Figure 5The figure shows a cross-sectional view of the diamond anvil press of the present invention. The diamond anvil press 8 provides a high-pressure environment and can be used for low-temperature and strong magnetic field electrical testing, and includes: a pair of upper diamond anvils 14 and lower diamond anvils 15 with the same table diameter, an upper anvil pad 12 for fixing the upper diamond anvil, a lower anvil pad 13 for fixing the lower diamond anvil, a boss slider 9 for fixing the upper anvil pad 12, a lower pad base 11 for fixing the lower anvil pad, a slider guide cylinder 10 for limiting the lateral movement of the boss slider 9 (the boss slider 9 and the slider guide cylinder 10 are designed with an interference fit to limit the lateral movement of the boss slider 9), a short upper pad fixing screw 20 for fixing the upper anvil pad 12 to the boss slider 9, and a long lower pad fixing screw 21 for fixing the lower anvil pad 12. The following components include: a lower pad fixing screw 21 fixed to the slider guide cylinder 10; a lower pad base fixing screw 19 for fixing the lower pad base 11 to the slider guide cylinder 10; a left-handed pressure screw 17 and a right-handed pressure screw 18 for adjusting the distance between the upper diamond anvil 14 and the lower diamond anvil 15; a limit screw 16 for controlling the distance between the boss slider 9 and the slider guide cylinder 10; a ring PCB circuit board 22 for electrical test leads fixed to the end face of the boss slider 9; and a fixing screw 23 for fixing the ring PCB circuit board 22 to the boss slider 9; and a quick-plug adapter for electrical testing, including a pin end 24 that mates with the diamond anvil press 8 and a socket base end 31 that mates with the press rotary table 1.

[0041] According to the present invention, the application environment is a low temperature and strong magnetic field, and the material used for all metal components of the diamond anvil press 1 is high-strength non-magnetic beryllium copper.

[0042] Preferably, the overall diameter of the assembled diamond anvil press 1 does not exceed 23 mm, the height does not exceed 37 mm, and the weight does not exceed 80 g.

[0043] Preferably, the pressure range that the diamond anvil press 1 can generate is 0 to 150 GPa, and the pressure calibration adopts a general fluorescence spectrum calibration method. Internal conical light holes are designed in the middle of the boss slider 9, the lower pad base 11, the upper anvil pad 12 and the lower anvil pad 13. The internal conical light holes are used as light paths during pressure calibration; the pressure is applied by tightening the left-handed pressure screw 17 and the right-handed pressure screw 18, so that the boss slider 9 slides downward relative to the slider guide cylinder 10, thereby continuously approaching the lower pad base 11, and finally reducing the distance between the upper diamond anvil 14 and the lower diamond anvil 15 to achieve an increase in pressure.

[0044] The diamond anvil press 8 and the pin end 24 are installed by using 8 M2.5 press fixing screws 29 with a length of 2.5 mm to tighten and fix them from the side threaded holes of the pin end 24, and make the upper end surface of the slider guide cylinder 10 flush with the upper surface of the adapter PCB circuit board 25 to ensure that the center of gravity of the diamond anvil press 8 is on the press rotation axis, thereby improving the angular accuracy.

[0045] The upper end surface of the pin end 24 is installed with a transfer PCB circuit board 25 for electrical connection and conduction, and the lower end surface is installed with a pin PCB circuit board 26 for electrical connection and conduction and welded with 12 conductive pins 30. The first PCB fixing screw 27 is used to fix the transfer PCB circuit board 25 to the upper end surface of the pin end 24, and the second PCB fixing screw 28 is used to fix the pin PCB circuit board 26 to the lower end surface of the pin end 24.

[0046] like Figure 2 As shown, the transfer PCB circuit board 25 is provided with 12 first electrode terminal blocks 38, which are sized at 1.5 mm × 1.5 mm and are used to electrically connect to the enameled copper wires led out from the sample; there are also 12 smaller second electrode terminal blocks 37, which are sized at 0.5 mm × 0.5 mm and are used to electrically connect to the pin PCB circuit board 26 through enameled copper wires by soldering;

[0047] The pin PCB circuit board 26 is welded with 12 gold-plated conductive pins 30 , with an outer diameter of φ0.5 mm and a length of 3 mm.

[0048] The adapter PCB circuit board 25 and the pin PCB circuit board 26 are electrically connected by soldering using enameled copper wire with a wire diameter of 80 μm.

[0049] The socket base end 31 is installed on the press rotary table 1, and a press rotary bearing hole 35 with a through hole diameter of φ4mm is opened in the middle position on both sides of the socket base end 31 for installing the press rotary shaft; the socket base end 31 is connected to the press rotary table 1 through the press rotary shaft and does not need to be disassembled during subsequent use.

[0050] A jack PCB circuit board 32 for electrical conduction and welded with a conductive socket 34 is installed on the lower end surface of the jack base end 31 , and the jack PCB circuit board 32 is fixed to the jack base end 31 using a third PCB circuit board fixing screw 33 .

[0051] On the socket PCB circuit board 32, there are 12 gold-plated conductive sockets 34 welded, and a retaining spring is provided in the hole. The depth of the hole is not less than 3mm and the inner diameter is φ0.5mm.

[0052] The jack PCB circuit board 32 is electrically connected to the sample rod signal line through an enameled copper wire with a wire diameter of 80 μm.

[0053] According to the angled diamond anvil cell high-voltage device for low-temperature, high-magnetic-field electrical testing required by the present invention, the total weight of the quick-plug adapter does not exceed 18 g.

[0054] The high-precision rotation function of the present invention is realized as follows: the diamond anvil press 8 is installed on the pin end 24, and then installed on the socket base end 31 assembled on the high-precision press rotating shaft, and finally the whole is loaded into the sample cavity of the low-temperature superconducting magnet system. The press rotating table 1 is mechanically connected to the stepper motor 2 through gears and a transmission shaft 7. The stepper motor 2 is connected to the motor controller 3 through a motor communication cable 5. The motor controller 3 is connected to a computer 4 installed with remote control software through a USB cable 6. Finally, continuous high-precision rotation control of the diamond anvil press 8 is realized through the remote control software.

[0055] The working temperature of the diamond anvil press 8 of the present invention is 1.5K to 380K, and the magnetic field range is -14T to 14T.

[0056] Figure 2 、 Figure 3 、 Figure 4 and Figure 5 Demonstrated the implementation of quick-plug electrical connections based on a diamond anvil press.

[0057] The diamond anvil press 8 and the pin end 24 are installed by using 8 M2.5 machine screws 20 with a length of 2.5 mm to tighten and fix them from the threaded holes on the side of the adapter seat, and keep the upper end surface of the slider guide cylinder 10 flush with the upper surface of the adapter PCB circuit board 25 to ensure that the center of gravity of the diamond anvil press 8 is on the press rotation axis.

[0058] The upper end surface of the pin end 24 is installed with a transfer PCB circuit board 25 for electrical conduction, and the lower surface is equipped with a pin PCB circuit board 26 for electrical conduction and welded with a conductive pin 30. The second electrode terminal block 37 on the upper surface of the transfer PCB circuit board 25 is connected to the conductive pin 30 by one-to-one soldering using enameled copper wire with a wire diameter of 80μm.

[0059] The transfer PCB circuit board 25 is electrically connected to the wire (platinum electrode) led out from the sample in the diamond anvil press 8 , and the sample is placed between the upper diamond anvil 14 and the lower diamond anvil 15 .

[0060] The lower end surface of the socket base end 31 is equipped with a socket PCB circuit board 32 for electrical conduction and welded with a conductive socket 34. The conductive socket 34 is electrically soldered to the electrical signal line on the rotating sample rod through an enameled copper wire with a wire diameter of 80μm.

[0061] The pin end 24 on which the diamond anvil press 8 is installed is inserted into the socket base end 31, so that the sample located on the end face of the lower diamond anvil 15 is conducted to the annular PCB circuit board 22 through the platinum electrode, and then to the adapter PCB circuit board 25 through the enameled copper wire, through the second electrode terminal block 37 and the first electrode terminal block 38, and then to the conductive pin 30 on the pin PCB circuit board 26 through the enameled copper wire, the conductive pin 30 is inserted into the conductive socket 34 on the socket PCB circuit board 32, and then to the signal line on the rotating sample rod (the rotating sample rod is hollow) through the enameled copper wire, and finally to the electrical connection to the measuring meter through the signal cable, thereby finally realizing electrical testing under high voltage environment.

[0062] like Figure 6 Figure 2 shows the measurement results of the resistance evolution of a sample as a function of rotation angle, using the diamond anvil angle high-voltage device of the present invention. The sample used was 2H-phase niobium disulfide. The measurement temperature was 2.8K, the applied pressure was ~4 GPa, and the applied magnetic field was 4 T. The relationship between the resistance evolution of the sample and the rotation angle was verified, demonstrating that the diamond anvil angle high-voltage device for low-temperature, high-magnetic-field electrical testing provided by the present invention can achieve high-precision rotation angle electrical testing under the combined extreme conditions of ultrahigh pressure, extremely low temperature, and high magnetic field.

[0063] The above describes the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions merely describe the principles of the present invention. Various changes and improvements may be made to the present invention without departing from the spirit and scope of the present invention. Such changes and improvements fall within the scope of the invention as claimed.

Claims

1. A diamond anvil angle high voltage device for low temperature and high magnetic field electrical testing, characterized in that: The invention comprises a press rotating table (1) placed in a low-temperature superconducting magnet sample cavity, a stepping motor (2) placed at room temperature, the stepping motor (2) being connected to a motor controller (3) via a motor communication cable (5), the motor controller (3) being connected to a computer (4) via a USB cable (6), the press rotating table (1) being mechanically connected to the stepping motor (2) via a transmission shaft (7); a quick plug-in adapter is installed on the press rotating table (1), a diamond anvil press (8) is arranged on the quick plug-in adapter, the quick plug-in adapter comprises a pin end (24) and a socket base end (31), a test sample is placed in the diamond anvil press (8); and a test sample is placed on the upper diamond anvil press. The test sample on the anvil surface of the anvil (14) is connected to the annular PCB circuit board (22) through an external platinum wire, and then connected to the first electrode terminal block (38) on the transfer PCB circuit board (25) through an enameled copper wire. The first electrode terminal block (38) is connected to the second electrode terminal block (37) on the pin PCB circuit board. The second electrode terminal block (37) is connected to the conductive pin (30) on the pin end (24) through the enameled copper wire. The conductive pin (30) is electrically connected to the conductive socket (34) on the socket base end (31) in a plug-in manner. The conductive socket (34) is externally connected to an external measuring meter through a signal line on a rotating sample rod, thereby finally achieving measurement of the electrical characteristics of the test sample.

2. The diamond anvil angle high voltage device for low temperature and high magnetic field electrical testing according to claim 1, characterized in that: The diamond anvil press (8) comprises: A pair of upper diamond anvils (14) and lower diamond anvils (15) with the same table diameter; An upper anvil pad (12) and a lower anvil pad (13) for fixing the upper and lower diamond anvils; A boss slider (9) for fixing the upper anvil pad; A lower pad base (11) for fixing the lower anvil pad; A slider guide cylinder (10) for limiting the lateral movement of the boss slider (9); A left-hand pressing screw (17) and a right-hand pressing screw (18) for adjusting the distance between the upper and lower diamond anvils; A ring-shaped PCB circuit board (22) fixed on a boss slider (9) and used for electrical test leads.

3. The diamond anvil angle high voltage device for low temperature and high magnetic field electrical testing according to any one of claims 1 to 2, characterized in that: The material of the diamond anvil cell press (8) is non-magnetic beryllium copper and can generate a pressure in the range of 0 to 150 GPa.

4. The diamond anvil angle high voltage device for low temperature and high magnetic field electrical testing according to claim 1, characterized in that: The diamond anvil press (8) is assembled on the pin end (24), and the pin end (24) and the socket base end (31) can be separated; The upper end surface of the pin end (24) is equipped with a transfer PCB circuit board (25) for electrical conduction, and the lower end surface is equipped with a pin PCB circuit board (26) for electrical conduction, and a conductive pin (30) is welded on the pin PCB circuit board (26); A socket PCB circuit board (32) for electrical conduction is installed on the lower end surface of the socket base end (31), and a conductive socket (34) is welded on the socket PCB circuit board (32); a press rotation bearing hole (35) is opened on the side of the socket base end (31), and the press rotation bearing hole (35) is a through hole.

5. The diamond anvil angle high voltage device for low temperature and high magnetic field electrical testing according to claim 4, characterized in that: The material of the pin end (24) and the socket base end (31) is brass.

6. The diamond anvil angle high voltage device for low temperature and high magnetic field electrical testing according to claim 4, characterized in that: The transfer PCB circuit board (25) is provided with a first electrode terminal block (38) for electrically connecting to a wire drawn from a sample in a press; and is also provided with a second electrode terminal block (37) for electrically connecting to a conductive pin (30) on a pin PCB circuit board (26); The surface of the conductive pin (30) is gold-plated; The transfer PCB circuit board (25) and the pin PCB circuit board (26) are connected by soldering using enameled copper wire; The surface of the conductive socket (34) is gold-plated, and a retaining spring is provided in the hole; The conductive pins (30) and the conductive sockets (34) are of the same number, and their positions and sizes match, ensuring electrical connection or disconnection.

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