High-precision optical lattice clock main vacuum cavity device

Abstract

The invention discloses a main vacuum cavity device of a high-precision optical lattice clock, which belongs to the field of metering instruments and comprises a special-shaped main vacuum cavity provided with a plurality of windows, interfaces and electrodes. A heat shield device is arranged in the special-shaped main vacuum cavity, an indium tin oxide conductive optical thin film is arranged on the side, close to the vacuum side in the special-shaped main vacuum cavity, of the window, the indium tin oxide conductive optical thin film is communicated with the special-shaped main vacuum cavity, and the inner surface of the special-shaped main vacuum cavity is coated with carbon nano tube ultra-black paint. A heat shield through hole is formed in the center of a heat shield body of the heat shield device, grooves are formed in the two sides of the heat shield body, film platinum resistors are installed on the grooves, the cold end of a Peltier is attached to one end of the heat shield body, the hot end of the Peltier is attached to one end of a heat conduction base, and the other end of the heat conduction base is installed on the inner surface of a special-shaped main vacuum cavity. The heat insulation layer is arranged on the outer surface of the heat shield body, direct-current stark frequency shift can be eliminated, and the uncertainty of black-body radiation frequency shift can be reduced to 10-19 orders of magnitude.

Description

Technical Field

[0001] This invention belongs to the field of measuring instruments, specifically relating to a high-precision optical lattice clock main vacuum cavity device. Background Technology

[0002] Optical lattice atomic clocks are among the candidates for the next generation of devices that reproduce the definition of the second, and they have already achieved 10-1 seconds. -19 The system uncertainty is on the order of magnitude. Thanks to their superior system performance, optical lattice atomic clocks are gradually playing an important role in the field of precision measurement. They are currently being used extensively in areas such as atomic structure research, relativistic geodesy, dark matter detection, testing the minute changes of fundamental physical constants over time, verifying general relativity, and temperature calibration. With further improvements in accuracy, their applications in these fields will become even more widespread, achieving measurement precision far exceeding that of traditional measurement techniques and methods.

[0003] However, for the most studied strontium and ytterbium optical lattice atomic clocks, the systematic uncertainty of blackbody radiation frequency shift is the most significant factor limiting their accuracy. Furthermore, the DC Stark effect is a system frequency shift term present in all optical atomic clocks; its time-varying characteristics mean that traditional evaluation methods cannot meet the requirements for long-term system operation, necessitating continuous assessment of its magnitude.

[0004] On the other hand, although the uncertainty in the assessment of the blackbody radiation frequency shift of the strontium optical lattice atomic clock has been reduced to 7.3 × 10⁻⁶, -19 However, this requires precise and complex temperature control of the entire massive vacuum device, combining highly accurate internal vacuum temperature measurement and finite element analysis. Such a technical solution is difficult to reproduce, unsuitable for portable or spaceborne optical lattice atomic clocks, and the blackbody radiation frequency shift needs to be corrected in real time using data from various sources. Reducing the uncertainty of the system's blackbody radiation frequency shift and eliminating DC Stark frequency shift have always been hot topics in optical lattice atomic clock research. Summary of the Invention

[0005] The purpose of this invention is to overcome the problem of being unable to reduce the uncertainty of the blackbody radiation frequency shift of the system and eliminate the DC Stark frequency shift, and to propose a high-precision optical lattice clock main vacuum cavity device.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: In a first aspect, the present invention provides a high-precision optical lattice clock main vacuum cavity device, including an irregularly shaped main vacuum cavity, on which multiple windows, interfaces and electrodes are provided; a thermal shield device is provided inside the irregularly shaped main vacuum cavity, and an indium tin oxide conductive optical film is provided on the side of the window near the vacuum inside the irregularly shaped main vacuum cavity, the indium tin oxide conductive optical film is in communication with the irregularly shaped main vacuum cavity, and the inner surface of the irregularly shaped main vacuum cavity is coated with a carbon nanotube ultra-black coating. The thermal shield device includes a thermal shield body, a Peltier, a thermally conductive base, a thermal insulation layer and a thin-film platinum resistance thermometer. A thermal shield through hole is opened in the center of the thermal shield body, and grooves are provided on both sides of the thermal shield body. The thin-film platinum resistance thermometer is installed in the grooves, the cold end of the Peltier is attached to one end of the thermal shield body, the hot end of the Peltier is attached to one end of the thermally conductive base, the other end of the thermally conductive base is installed on the inner surface of the irregularly shaped main vacuum cavity, and the thermal insulation layer is provided on the outer surface of the thermal shield body.

[0007] Furthermore, the main body of the heat shield is made of pure copper, the inner wall of the heat shield through hole is the inner surface of the heat shield, and a copper oxide layer is set on the inner surface of the heat shield.

[0008] Furthermore, the heat shield device also includes a mounting bracket, the pressure surface of which is on the other end of the heat shield body, and the Peltier heat end is pressed against one end of the heat-conducting base by the mounting bracket.

[0009] Furthermore, the main body of the heat shield is axially parallel to the irregularly shaped main vacuum cavity, and the center of the main body of the heat shield is horizontally offset from the center of the main vacuum cavity.

[0010] Furthermore, the Peltier and thin-film platinum resistance thermometer actively control the temperature of the thermal screen body, and the heat from the Peltier is conducted to the irregularly shaped main vacuum cavity for release through the heat-conducting base.

[0011] Furthermore, the irregularly shaped main vacuum cavity is made of titanium metal, and the interior of the irregularly shaped main vacuum cavity is a cylindrical cavity.

[0012] Furthermore, each of the two planes of the irregularly shaped main vacuum cavity is provided with a window, and the side curved surface of the irregularly shaped main vacuum cavity is provided with several windows.

[0013] Furthermore, the irregularly shaped main vacuum cavity is grounded to form a Faraday cage.

[0014] Furthermore, a high-transmittance optical thin film is provided on the side of the window away from the vacuum inside the irregularly shaped main vacuum cavity.

[0015] Secondly, the present invention provides a method for operating a high-precision optical lattice clock main vacuum cavity device, comprising the following steps: The irregularly shaped main vacuum cavity is grounded, and the indium tin oxide conductive optical film deposited on the inner side of the window is connected to the cavity. The entire cavity forms a Faraday cage, which is used to shield the external DC electric field and avoid the accumulation of stray charges on the inner surface of the cavity. The temperature signal of the hot screen body is collected by a thin-film platinum resistance thermometer. The temperature signal is transmitted to the external temperature control module through the electrodes. The external temperature control module supplies power to the Peltier through the electrodes according to the temperature signal. The heat generated by the Peltier is conducted to one end of the heat-conducting base through the hot end, and then diffused to the irregular main vacuum cavity through the other end of the heat-conducting base for release. At the same time, the heat insulation layer on the outer surface of the hot screen body is used to isolate external heat exchange and maintain the temperature stability of the hot screen body. Two beams of lattice light are incident on each other through a pair of windows of the irregular main vacuum cavity. Both beams of lattice light pass through the through hole in the center of the thermal screen body and interfere with each other in space to form an optical lattice. Atoms are moved to the area of ​​the hot screen body by moving optical lattice method, and the clock transition frequency of the atoms is detected by incident clock laser.

[0016] Compared with the prior art, the present invention has the following beneficial technical effects: This invention proposes a high-precision optical lattice clock master vacuum cavity device that can eliminate DC Stark frequency shift and reduce the uncertainty of blackbody radiation frequency shift to 10. -19 In a large-scale optical lattice clock main vacuum cavity device, the DC Stark effect is caused by stray charges adhering to the insulator inside the main vacuum cavity. Therefore, eliminating the DC Stark effect requires making the inner surface of the cavity conductive and grounded. This invention achieves good conductivity while maintaining light transmission by depositing an indium tin oxide conductive optical film on the vacuum surface of all transparent windows. Furthermore, the inner surface of the main vacuum cavity is blackened with a carbon nanotube super-black coating, increasing emissivity while also providing excellent conductivity. Grounding the entire main vacuum cavity forms a Faraday cage, which not only prevents stray charges from accumulating on the vacuum inner surface but also shields the atomic transition frequencies from the influence of the ambient DC electric field. To reduce the uncertainty of blackbody radiation frequency shift, this invention employs a temperature-controlled thermal screen to provide a stable and uniform thermal radiation environment for the atoms. The thermal screen has a through-hole in its center to transmit lattice light. The temperature of the thermal screen is measured by a precisely calibrated thin-film platinum resistance thermometer and actively controlled by a Peltier sensor. An insulation layer is installed on the outside of the thermal shield to isolate it from convective and radiative heat exchange with the environment, achieving more stable and uniform temperature control. Before clock transition detection, atoms are moved from the center of the main vacuum cavity to the interior of the thermal shield using a moving optical lattice technique, and then the clock transition frequency is detected. After clock transition detection, atoms return to the center of the main vacuum cavity again using the moving optical lattice technique to detect the transition probability. By controlling the temperature of the thermal shield at -30°C or even lower, this invention reduces the uncertainty of blackbody radiation frequency shift to 5 × 10⁻⁶. -19 The following potential.

[0017] This invention fundamentally eliminates the DC Stark frequency shift caused by stray charges accumulated on the inner surface of the main vacuum cavity or by external DC electric fields. This not only improves the accuracy of the optical lattice atomic clock but also enhances its long-term operational capability, as it eliminates the need for frequent calibration of the DC Stark frequency shift's impact on the system. The uncertainty in assessing the blackbody radiation frequency shift of the optical lattice clock can be reduced to 5 × 10⁻⁶. -19 Even lower. This invention is insensitive to changes in external temperature and has the ability to operate outdoors. It can be applied not only to high-performance optical lattice atomic clocks operating in laboratory environments, but also to portable and spaceborne optical lattice atomic clocks. Attached Figure Description

[0018] The accompanying drawings described herein are for illustrative purposes only and are not intended to limit the scope of the invention in any way. Furthermore, the shapes and proportions of the components in the drawings are merely illustrative to aid in understanding the invention and do not specifically limit the shapes and proportions of the components of the invention.

[0019] In the attached diagram: Figure 1 This is a front view schematic diagram of the structure of a high-precision optical lattice clock main vacuum cavity device according to one embodiment of the present invention.

[0020] Figure 2 This is a schematic diagram of one side of a high-precision optical lattice clock main vacuum cavity device according to one embodiment of the present invention. Figure 3 This is a schematic diagram of one side structure of a high-precision optical lattice clock main vacuum cavity device in one embodiment of the present invention.

[0021] Figure 4 This is a schematic diagram of the other side of a high-precision optical lattice clock main vacuum cavity device in one embodiment of the present invention.

[0022] Figure 5 This is a cross-sectional structural diagram of a high-precision optical lattice clock main vacuum cavity device according to one embodiment of the present invention.

[0023] Figure 6 This is a schematic diagram of the thermal screen device structure of a high-precision optical lattice clock main vacuum cavity device in one embodiment of the present invention.

[0024] Figure 7 This is a cross-sectional structural schematic diagram of the thermal screen device of a high-precision optical lattice clock main vacuum cavity device in one embodiment of the present invention.

[0025] In this diagram, 1 represents the first window, 2 the second window, 3 the third window, 4 the fourth window, 5 the fifth window, 6 the sixth window, 7 the seventh window, 8 the eighth window, 9 the ninth window, 10 the tenth window, 11 the eleventh window, 12 the twelfth window, 13 the thirteenth window, 14 the fourteenth window, 15 the fifteenth window, 16 the sixteenth window, 17 the seventeenth window, 18 the eighteenth window, 19 the nineteenth window, 20 the twentieth window, 21 the twenty-first window, 22 the twenty-second window, 23 the twenty-third window, and 24 the... The system consists of 24 windows, 25 being the 25th window, 26 being the first interface, 27 being the second interface, 28 being the third interface, 29 being the first electrode, 30 being the second electrode, 31 being the inner surface of the vacuum chamber, 32 being the heat shield device, A1 being the first heat insulation layer, A2 being the second heat insulation layer, A3 being the third heat insulation layer, A4 being the fourth heat insulation layer, A5 being the fifth heat insulation layer, A6 being the first thin-film platinum resistance thermometer, A7 being the second thin-film platinum resistance thermometer, A8 being the mounting bracket, A9 being the main body of the heat shield, A10 being the Peltier, A11 being the thermally conductive base, A12 being the inner surface of the heat shield, and A13 being the through hole of the heat shield. Detailed Implementation

[0026] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0027] Example 1 A high-precision optical lattice clock main vacuum cavity device includes an irregularly shaped main vacuum cavity with multiple windows, interfaces, and electrodes. A heat shield device 32 is installed inside the irregularly shaped main vacuum cavity. An indium tin oxide (ITO) conductive optical film is installed on the side of the window closest to the vacuum inside the irregularly shaped main vacuum cavity, and the ITO conductive optical film is in communication with the irregularly shaped main vacuum cavity. The inner surface of the irregularly shaped main vacuum cavity is coated with a carbon nanotube ultra-black coating. The heat shield device 32 includes a heat shield body A9 and a... The system consists of a Peltier A10, a thermally conductive base A11, an insulation layer, and a thin-film platinum resistance thermometer. The thermal screen body A9 has a thermal screen through-hole A13 in the center. The thermal screen body A9 has grooves on both sides, and the thin-film platinum resistance thermometer is installed in the grooves. The cold end of the Peltier A10 is attached to one end of the thermal screen body A9, and the hot end of the Peltier A10 is attached to one end of the thermally conductive base A11. The other end of the thermally conductive base A11 is installed on the inner surface 31 of the irregularly shaped main vacuum cavity. The insulation layer is provided on the outer surface of the thermal screen body A9.

[0028] This embodiment features a uniquely shaped main vacuum cavity with multiple windows and electrodes, facilitating optical operation and electrical connections. The indium tin oxide conductive optical film inside the windows ensures both optical performance and electrical conductivity, maintaining a stable electric field through its connection with the cavity. The carbon nanotube ultra-black coating on the inner surface effectively reduces stray light and improves measurement accuracy. The thermal shield device includes openings in the main body and grooves for mounting a thin-film platinum resistance thermometer, enabling precise temperature measurement. A Peltier cold end is attached to the main body of the thermal shield, while the hot end connects to a heat-conducting base, efficiently regulating the thermal shield temperature. The insulation layer reduces heat loss and maintains internal temperature stability. Through these design features, the overall device creates a stable, low-stray-light, and temperature-controllable environment for the optical lattice clock, significantly improving its measurement accuracy and stability. This has significant application value in time and frequency metrology, fundamental physics research, and other fields, providing a reliable guarantee for high-precision measurement and research.

[0029] The main body of the heat shield, A9, is made of pure copper. The inner wall of the heat shield through-hole, A13, is the inner surface of the heat shield, A12, which is covered with a copper oxide layer. The main body of the heat shield is made of pure copper, which has high thermal conductivity. The copper oxide layer on the inner wall of the through-hole enhances heat resistance and oxidation resistance, extending the service life of the heat shield.

[0030] The heat shield device 32 also includes a mounting bracket A8. The pressure surface of the mounting bracket A8 is on the other end of the heat shield body A9. The hot end of the Peltier A10 and one end of the heat-conducting base A11 are pressed together by the mounting bracket A8. The mounting bracket A8 presses the heat shield together with its pressure surface, so that the hot end of the Peltier A10 and the heat-conducting base A11 are in close contact, improving heat conduction efficiency and device stability.

[0031] The heat shield body A9 is axially parallel to the irregularly shaped main vacuum chamber, and the center of the heat shield body A9 is horizontally offset from the center of the main vacuum chamber. This axial parallelism and horizontal center offset optimizes the spatial layout, facilitates installation and maintenance, and improves heat shielding and temperature uniformity.

[0032] The Peltier A10 and thin-film platinum resistance thermometer provide active temperature control for the thermal screen body A9, and the heat from the Peltier A10 is conducted to the irregularly shaped main vacuum cavity for release through the heat-conducting base A11. Active temperature control precisely regulates the thermal screen temperature, ensuring stability; the heat is transferred to the cavity for release through the heat-conducting base, improving heat dissipation efficiency and system reliability.

[0033] The irregularly shaped main vacuum chamber is made of titanium metal, and its interior is a cylindrical cavity. The titanium metal irregularly shaped cavity has high strength and corrosion resistance, and the cylindrical internal structure is simple, which is conducive to vacuuming and can create a stable vacuum environment.

[0034] The irregularly shaped main vacuum cavity has one window on each of its two planes, and several windows on its side curved surface. This multi-window design on the two planes and side curved surface meets the needs of observation and operation from different orientations, enhancing the cavity's functionality and experimental convenience.

[0035] The irregularly shaped main vacuum cavity is grounded to form a Faraday cage. Grounding the irregularly shaped main vacuum cavity to form a Faraday cage can effectively shield external electromagnetic interference and ensure a stable and reliable internal experimental environment.

[0036] A high-transmittance optical film is installed on the side of the window away from the vacuum inside the irregularly shaped main vacuum cavity. The high-transmittance optical film is located on the outside of the window, which can ensure high light transmittance and isolate external impurities, maintaining a pure environment inside the cavity.

[0037] Example 2 A method for operating a high-precision optical lattice clock main vacuum cavity device, comprising the following steps: The irregularly shaped main vacuum cavity is grounded, and the indium tin oxide conductive optical film deposited on the inner side of the window is connected to the cavity. The entire cavity forms a Faraday cage, which is used to shield the external DC electric field and avoid the accumulation of stray charges on the inner surface of the cavity. Temperature signals of the thermal screen body A9 are collected by a thin-film platinum resistance thermometer. The temperature signals are transmitted to an external temperature control module through electrodes. The external temperature control module supplies power to the Peltier A10 through electrodes based on the temperature signals. The heat generated by the Peltier A10 is conducted through the hot end to one end of the heat-conducting base A11, and then diffused to the irregularly shaped main vacuum cavity through the other end of the heat-conducting base A11 for release. At the same time, the heat insulation layer on the outer surface of the thermal screen body A9 is used to isolate external heat exchange and maintain the temperature stability of the thermal screen body A9. Two beams of lattice light are incident on each other through a pair of windows of the irregular main vacuum cavity. Both beams of lattice light pass through the through hole A13 of the heat shield body A9 and interfere with each other in space to form an optical lattice. Atoms are transferred to the region where the thermal screen body A9 is located using a moving optical lattice method, and the clock transition frequency of the atoms is detected by incident clock laser.

[0038] In this embodiment, the irregularly shaped main vacuum cavity is grounded, and a Faraday cage is formed using an indium tin oxide conductive optical thin film. This effectively shields the external DC electric field and prevents stray charges from accumulating on the inner surface of the cavity, creating a stable electromagnetic environment for the atomic clock operation and reducing the impact of external interference on measurement accuracy. A temperature control system composed of a thin-film platinum resistance thermometer, an external temperature control module, and a Peltier precisely collects and adjusts the temperature of the thermal shield, maintaining temperature stability in conjunction with the insulation layer. This ensures the stability of the optical lattice and improves the frequency stability of the atomic clock. Lattice light enters through a window to form an optical lattice. Atoms are then moved to specific regions by shifting the optical lattice to detect clock transition frequencies. This design allows for more complete interaction between atoms and the optical lattice, enabling more accurate measurement of atomic clock transition frequencies. This improves the overall accuracy and reliability of the optical lattice clock, meeting the requirements for high-precision time measurement.

[0039] Example 3 like Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 As shown, a high-precision optical lattice clock main vacuum cavity device includes an irregularly shaped main vacuum cavity, a flange with a light-transmitting window on the main vacuum cavity, and an electrode flange for electrical signal transmission. Inside the main vacuum cavity is a heat shield device with active temperature control, designed to provide a stable and uniform thermal radiation environment for atoms. The heat shield device consists of a heat shield body, a Peltier, a thermally conductive base, an insulation layer, a thin-film platinum resistance thermometer, and a fixing bracket. The heat shield body is made of pure copper with good thermal conductivity, and has a small through-hole in its center for transmitting lattice light. A conductive optical thin film is deposited on the side of the light-transmitting window closest to the inner vacuum, and it is connected to the entire main vacuum cavity by welding to the flange. The inner surface of the main vacuum cavity is blackened with a conductive ultra-black coating to increase surface emissivity, while the inner wall of the light-transmitting hole of the heat shield is blackened by high-temperature oxidation. By grounding the main vacuum cavity, the entire device forms a Faraday cage, which can eliminate the DC Stark frequency shift caused by the external DC electric field and stray charges accumulated on the inner vacuum surface. By using a moving optical lattice technique to move atoms within a thermal screen for clock transition frequency detection, the uncertainty in blackbody radiation frequency shift can be reduced to 10. -19 This invention combines shallow optical lattice technology, Faraday cage technology, moving optical lattice technology, and technology based on temperature-controlled thermal screens to reduce the uncertainty of blackbody radiation frequency shift, thereby achieving a high-precision optical lattice atomic clock. Theoretically, the final system uncertainty of the optical lattice clock can be reduced to the order of E-19. The device designed in this invention can operate in environments outside the laboratory and can be applied to portable or spaceborne optical lattice atomic clocks.

[0040] The irregularly shaped main vacuum chamber is equipped with flanges 1-25 on the right side with light-transmitting windows, three interfaces 26-28 for connecting with other components, and two electrode flanges 29-30 for transmitting electrical signals. A heat shield device 32 is fixed on the inner vacuum surface 31. The heat shield device includes a heat shield body A9, a Peltier A10, a thermally conductive base A11, and thermal insulation layers A1-A5. The heat shield body A9 has through holes A13 and thin-film platinum resistance thermometers A6-A7. The inner surface of the main vacuum chamber is blackened with a conductive coating, and the side of the light-transmitting windows facing the inner vacuum is coated with a conductive optical film. The entire main vacuum chamber is made of non-magnetic conductive metal and grounded. The heat shield device is installed inside the main vacuum chamber. The heat shield body is made of pure copper, and its temperature is sampled by the thin-film platinum resistance thermometer and actively controlled by the Peltier. The heat from the Peltier is released through the thermally conductive base connected to the main vacuum chamber. Thermal insulation plates are fixed around the heat shield body to isolate it from heat exchange with the surrounding environment. The irregularly shaped main vacuum chamber is machined from pure titanium and has a height of 116 mm. An internal cylindrical space with a diameter of 160 mm and a height of 64 mm is provided for installing a heat shield device. A CF16 flange is installed on the top and bottom of the main vacuum chamber, with a light-transmitting window diameter of 16 mm. Twenty-two CF16 flanges, each with a light-transmitting window diameter of 16 mm, are located on the side of the main vacuum chamber; one CF35 flange with a light-transmitting window diameter of 35 mm is also present; three through-hole interfaces with a diameter of 35 mm are provided, each with a standard knife edge for connecting to other standard-sized devices; two electrode flanges are also provided, with knife edges matching the standard knife edges of the CF16 flanges. The main body of the heat shield has a maximum length of 30 mm, a maximum height of 3 mm, and a maximum width of 8 mm. A through-hole with a diameter of 1 mm and a length of 30 mm is located in the center. The outer surface of the heat shield is insulated from external heat exchange by a 1 mm thick polyetheretherketone (PEEK) plate. A 1 mm long and 0.5 mm wide groove is provided on each side of the heat shield to install a thin-film platinum resistance thermometer. The bottom of the heat shield is tightly attached to the cold end of a fourth-order Peltier, which is 10.76 mm long and 6.94 mm wide. The bottom is 28.44 mm long and 21.87 mm wide. The hot end of the fourth-order Peltier is tightly attached to the heat-conducting base and pressed firmly by an anodized black aluminum mounting bracket. The heat-conducting base is made of pure copper and is fixed to the black surface of the main vacuum chamber with four screws. Screw holes are also provided on the base to secure the Peltier.

[0041] exist Figure 5 , Figure 6 , Figure 7In the design, the outer diameter of the main vacuum chamber is 296 mm and the height is 116 mm; the hollowed-out part inside has a diameter of 160 mm and a height of 64 mm. The inner vacuum surface 31 is coated with carbon nanotube ultra-black paint to reduce the reflectivity of the inner surface to below 0.1%. The main vacuum chamber is made of titanium, which has the advantages of being non-magnetic, having a low outgassing rate, and being lightweight.

[0042] The main vacuum chamber is equipped with 25 flanges with transparent windows. Flanges 1 through 24 are standard CF16 flanges with a transparent window diameter of 16mm, while flange 25 is a standard CF35 flange with a transparent window diameter of 35mm. The transparent windows are made of fused silica glass, with a diameter of 18mm and a thickness of 2mm. All transparent windows have an indium tin oxide conductive optical film deposited on the side closest to the inner vacuum, while a high-transmittance optical film is deposited on the side furthest from the vacuum, covering a transmission wavelength range of 460nm to 850nm.

[0043] The main vacuum chamber is equipped with interfaces 26-28, each with a through-hole diameter of 35 mm, for connecting to other components, including bellows and ion pumps. Additionally, flanges 29 and 30 with electrodes are provided, each containing four titanium electrodes insulated from the outside environment by ceramic. Power supply to the Peltier A10 and resistance measurements of the thin-film platinum resistance thermometers A6 and A7 are achieved through connections to these electrodes.

[0044] Inside the main vacuum chamber, a heat shield device 31 is installed. The heat shield device mainly consists of five parts: heat insulation layers A1-A5; a fixing frame A8; the heat shield body A9; a Peltier A10; and a heat-conducting base A11. The heat shield body A9 is made of pure copper, with a total length of 30mm, a maximum width of 8mm, and a maximum height of 3mm. A through-hole A13, 30mm long and 1mm in diameter, is located in the center of the heat shield body A9. The inner surface A12 of the through-hole A13 is formed with a copper oxide layer through high-temperature oxidation to reduce emissivity. The heat shield insulation layer is made of polyetheretherketone (PEEK), with a thickness of 1mm, and its dimensions perfectly fit the heat shield body A9. A groove, 1mm long and 0.5mm wide, is provided on each side of the heat shield to install thin-film platinum resistance thermometers A6 and A7. One side of the heat shield body is tightly fitted with the cold end of a fourth-order Peltier A10. The cold end of the fourth-order Peltier is 10.76mm long and 6.94mm wide, while the hot end is 28.44mm long and 21.87mm wide. The hot end of the fourth-order Peltier is tightly fitted with the heat-conducting base A11. The heat-conducting base is made of pure copper and is fixed to the inner surface 31 of the main vacuum chamber, meaning that the heat generated by the Peltier is ultimately released through the main vacuum chamber. The center height of the heat shield body A9 is consistent with the center height of the side of the main vacuum chamber, and the center position of the heat shield body A9 is 10mm away from the center position of the main vacuum chamber.

[0045] The fourth-order Peltier A10 is powered by a temperature control module manufactured by the National Institute of Metrology of China. The temperature of the thermal screen body A9 is collected by a thin-film platinum resistance thermometer A6 and fed back to the temperature control module, ultimately achieving active temperature control of the thermal screen body A9. The target temperature for temperature control is set to 0°C. The temperature of the thermal screen body is further monitored by another thin-film platinum resistance thermometer A7. The example demonstrated in this invention shows that the maximum temperature fluctuation of the thermal screen body A9 can be controlled within 3 mK, and the temperature difference between the thin-film platinum resistance thermometers A6 and A7 is less than 2 mK. The uncertainty of the frequency shift of blackbody radiation caused by these temperature fluctuations and gradients is less than 3 × 10⁻⁶. -19 .

[0046] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A high-precision optical lattice clock main vacuum cavity device, characterized in that, The device includes an irregularly shaped main vacuum cavity, which is provided with multiple windows, interfaces, and electrodes. A heat shield device (32) is installed inside the irregularly shaped main vacuum cavity. An indium tin oxide conductive optical film is installed on the side of the window closest to the vacuum inside the irregularly shaped main vacuum cavity. The indium tin oxide conductive optical film is in communication with the irregularly shaped main vacuum cavity. The inner surface of the irregularly shaped main vacuum cavity is coated with a carbon nanotube ultra-black coating. The heat shield device (32) includes a heat shield body (A9), a Peltier (A10), a heat-conducting base (A11), and an insulating... The thermal layer and the thin-film platinum resistance thermometer are provided. The thermal screen body (A9) has a thermal screen through hole (A13) in the center. The thermal screen body (A9) has grooves on both sides. The thin-film platinum resistance thermometer is installed on the grooves. The cold end of the Peltier (A10) is attached to one end of the thermal screen body (A9). The hot end of the Peltier (A10) is attached to one end of the heat-conducting base (A11). The other end of the heat-conducting base (A11) is installed on the inner surface (31) of the irregular main vacuum cavity. The insulation layer is provided on the outer surface of the thermal screen body (A9).

2. The high-precision optical lattice clock main vacuum cavity device according to claim 1, characterized in that, The main body of the heat shield (A9) is made of pure copper, and the inner wall of the heat shield through hole (A13) is the inner surface of the heat shield (A12), and the inner surface of the heat shield (A12) is provided with a copper oxide layer.

3. The high-precision optical lattice clock main vacuum cavity device according to claim 1, characterized in that, The heat shield device (32) also includes a fixing frame (A8), the pressure surface of which is on the other end of the heat shield body (A9), and the hot end of the Peltier (A10) is pressed against one end of the heat-conducting base (A11) by the fixing frame (A8).

4. The high-precision optical lattice clock main vacuum cavity device according to claim 1, characterized in that, The heat shield body (A9) is axially parallel to the irregularly shaped main vacuum cavity, and the center of the heat shield body (A9) is horizontally offset from the center of the main vacuum cavity.

5. The high-precision optical lattice clock main vacuum cavity device according to claim 1, characterized in that, The Peltier (A10) and the thin-film platinum resistance thermometer actively control the temperature of the thermal screen body (A9), and the heat from the Peltier (A10) is conducted to the irregularly shaped main vacuum cavity through the heat-conducting base (A11) for release.

6. The high-precision optical lattice clock main vacuum cavity device according to claim 1, characterized in that, The irregularly shaped main vacuum cavity is made of titanium, and the interior of the irregularly shaped main vacuum cavity is a cylindrical cavity.

7. The high-precision optical lattice clock main vacuum cavity device according to claim 1, characterized in that, The irregularly shaped main vacuum cavity has a window on each of its two planes, and several windows are provided on the side curved surface of the irregularly shaped main vacuum cavity.

8. The high-precision optical lattice clock main vacuum cavity device according to claim 1, characterized in that, The irregularly shaped main vacuum cavity is grounded to form a Faraday cage.

9. The high-precision optical lattice clock main vacuum cavity device according to claim 1, characterized in that, A high-transmittance optical thin film is provided on the side of the window away from the vacuum inside the irregularly shaped main vacuum cavity.

10. A method for operating a high-precision optical lattice clock main vacuum cavity device, characterized in that, Using the high-precision optical lattice clock main vacuum cavity device according to any one of claims 1-9 includes the following steps: The irregularly shaped main vacuum cavity is grounded, and the indium tin oxide conductive optical film deposited on the inner side of the window is connected to the cavity. The entire cavity forms a Faraday cage, which is used to shield the external DC electric field and avoid the accumulation of stray charges on the inner surface of the cavity. Temperature signals from the thermal shield body (A9) are collected by a thin-film platinum resistance thermometer. These signals are then transmitted to an external temperature control module via electrodes. The external temperature control module supplies power to the Peltier (A10) via electrodes based on the temperature signals. The heat generated by the Peltier (A10) is conducted through its hot end to one end of the heat-conducting base (A11), and then diffuses through the other end of the heat-conducting base (A11) to the irregularly shaped main vacuum cavity for release. Simultaneously, the insulation layer on the outer surface of the thermal shield body (A9) is used to isolate external heat exchange and maintain the temperature stability of the thermal shield body (A9). Two beams of lattice light are incident on each other through a pair of windows of the irregular main vacuum cavity. Both beams of lattice light pass through the through hole (A13) in the center of the thermal screen body (A9) and interfere with each other in space to form an optical lattice. Atoms are transferred to the area where the hot screen body (A9) is located by moving optical lattice method, and the clock transition frequency of the atoms is detected by incident clock laser.

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