A cold atomic clock light detection device for eliminating the influence of microwave leakage

Abstract

The application discloses a cold atomic clock light detection device capable of eliminating microwave leakage influence, and belongs to the field of high-end equipment manufacturing, which comprises a detection zone main body, a detection light assembly, a heavy pumping light assembly, a state selection pushing light assembly and a fluorescence collection assembly, a chamber is arranged in the detection zone main body, a perforation for passing through a cold atom group is arranged on the upper surface of the detection zone main body, the detection light assembly comprises a first metal shielding box, an upper energy level detection light lens barrel and a lower energy level detection light lens barrel, the first metal shielding box is installed on the detection zone main body, the upper energy level detection light lens barrel and the lower energy level detection light lens barrel are both located in the first metal shielding box, two first cutoff waveguides are arranged on the side of the first metal shielding box away from the detection zone main body, an optical fiber is arranged in each first cutoff waveguide, two first reflectors are arranged in the detection zone main body, and the two first reflectors correspond to the upper energy level detection light lens barrel and the lower energy level detection light lens barrel respectively.

Description

Technical Field

[0001] This invention belongs to the field of high-end equipment manufacturing technology, specifically relating to a cold atom clock optical detection device for eliminating the effects of microwave leakage. Background Technology

[0002] With the development and maturation of cold atom-related technologies, high-precision cold atom microwave clocks utilizing cold atom interferometry have surpassed the performance of traditional hot atom clocks. They have become core devices in various countries' time and frequency systems, satellite navigation, space station time and frequency systems, gravitational wave detection, and quantum precision measurement. Examples include cesium atomic fountain clocks, which serve as time reference devices for various countries; rubidium atomic fountain clocks, a new type of timekeeping atomic clock for timekeeping systems and satellite navigation ground station time and frequency systems; and small cold atom clocks for space station time and frequency systems.

[0003] Currently, common cold atom clocks mainly utilize microwaves fed into a microwave resonant cavity to excite cold atoms to undergo transitions. By taking advantage of the different transition probabilities of atoms at different frequencies, an external frequency oscillator is locked to the frequency spectrum line of the atomic transition energy level based on automatic control technology, thereby achieving the output of a time and frequency signal with atomic stability.

[0004] Theoretically, the fed microwaves only exist inside the microwave resonant cavity. When there are leaked microwaves outside the microwave resonant cavity along the path of the cold atom (these leaked microwaves can come from the microwave resonant cavity itself, the microwave feed source, the feed line, etc.), it will affect the accuracy and stability of the cold atom clock and restrict its performance.

[0005] Cold atom clocks typically use fluorescence detection to obtain atomic transition probabilities. Detection light from the detector tube passes through a glass window on the detector body and is reflected by an opposite mirror, forming a standing wave inside the detector body. When cold atoms interact with microwaves and fall into the detector body, they emit fluorescence upon passing through the standing wave. This fluorescence is focused onto a photodetector by the fluorescence collection tube of the detector body and converted into a voltage. Since two energy levels need to be detected, typically two detection standing wave beams are used, with a repumped standing wave beam in between. However, besides detecting atomic transition probabilities, the detector body itself is also part of the cold atom's path. Therefore, when leakage microwaves exist around the detector body, these leakage microwaves can enter the detector body through the detector tube, the fluorescence collection tube, and the connections between these tubes and optical fibers and signal lines, inevitably affecting the performance of the cold atom clock.

[0006] Traditional methods for suppressing the effects of microwave leakage in the detection region employ techniques such as microwave interferometry switches and microwave frequency shifting. However, these methods and devices require precise measurement of microwave phase changes and accurate timing control, and are subject to stringent environmental conditions, especially temperature variations. This increases the complexity of cold atom clocks and hinders their future industrialization. Therefore, there is an urgent need for a cold atom clock optical detection device with a simple structure and strong environmental adaptability to eliminate the effects of microwave leakage. Summary of the Invention

[0007] To address the aforementioned problems in the prior art, this invention provides a cold atom clock optical detection device that eliminates the effects of microwave leakage. The technical problem to be solved by this invention is achieved through the following technical solution:

[0008] In a first aspect, the present invention provides a cold atom clock optical detection device for eliminating the influence of microwave leakage, comprising a detection area body and a detection optical component, a re-pumping optical component, a selective push optical component and a fluorescence collection component mounted on the detection area body. The detection area body has a cavity inside, and the upper surface of the detection area body has a perforation for passing through the cold atom cluster, the perforation being connected to the cavity.

[0009] The detection light assembly, the selective push light assembly, the re-pump light assembly, and the fluorescence collection assembly are arranged sequentially along the circumference of the main body of the detection area. The detection light assembly and the re-pump light assembly are arranged opposite each other, and the selective push light assembly and the fluorescence collection assembly are arranged opposite each other.

[0010] The probe light assembly includes a first metal shielding box, an upper-level probe light tube, and a lower-level probe light tube. The first metal shielding box is installed on the main body of the probe region. The upper-level probe light tube and the lower-level probe light tube are both located inside the first metal shielding box. Two first cutoff waveguides are provided on the side of the first metal shielding box away from the main body of the probe region. Each first cutoff waveguide contains an optical fiber. The optical fibers in the two first cutoff waveguides are respectively connected to the upper-level probe light tube and the lower-level probe light tube.

[0011] The main body of the detection zone is equipped with two first reflecting mirrors, which correspond to the upper energy level probe light tube and the lower energy level probe light tube, respectively.

[0012] In one embodiment of the present invention, the redraw optical transport assembly includes a second metal shielding box and a redraw optical transport lens tube. The second metal shielding box is installed on the main body of the detection area, and the redraw optical transport lens tube is located inside the second metal shielding box. A second cutoff waveguide is provided on the side of the second metal shielding box away from the main body of the detection area. An optical fiber is provided in the second cutoff waveguide, and the optical fiber in the second cutoff waveguide is connected to the redraw optical transport lens tube.

[0013] The main body of the detection area is equipped with a second reflector, which corresponds to the re-extraction transport mirror tube.

[0014] In one embodiment of the present invention, the optical axes of the upper energy level probe optical mirror tube, the lower energy level probe optical mirror tube, and the pump optical mirror tube are parallel to each other, and the optical axis of the pump optical mirror tube is located between the optical axes of the upper energy level probe optical mirror tube and the lower energy level probe optical mirror tube.

[0015] The first reflector is located on the side closer to the pumped light assembly, and the two first reflectors are coaxially arranged with the upper level probe light tube and the lower level probe light tube, respectively. The second reflector is located on the side closer to the probe light assembly, and the second reflector is coaxially arranged with the pumped light tube.

[0016] In one embodiment of the present invention, a first adapter plate is further included, which is detachably connected to the detection area body, and a first metal shielding box is detachably connected to the first adapter plate;

[0017] An indium wire sealing ring is provided between the first adapter plate and the main body of the detection area, and an indium wire sealing ring is provided between the first adapter plate and the first metal shielding box. The first adapter plate has two first through holes, which correspond to the upper energy level detector light tube and the lower energy level detector light tube, respectively. Both sides of the first adapter plate are provided with annular grooves for accommodating the indium wire sealing rings. The side of the main body of the detection area facing the first adapter plate is provided with an annular groove for accommodating the indium wire sealing rings, and the side of the first metal shielding box facing the first adapter plate is provided with an annular groove for accommodating the indium wire sealing rings.

[0018] In one embodiment of the present invention, a second adapter plate is further included, which is detachably connected to the detection area body, and a second metal shielding box is detachably connected to the second adapter plate.

[0019] An indium wire sealing ring is provided between the second adapter plate and the main body of the detection area, and an indium wire sealing ring is provided between the second adapter plate and the second metal shielding box. The second adapter plate is provided with a second through hole, which corresponds to the re-extraction transport lens tube. Both sides of the second adapter plate are provided with annular grooves for accommodating the indium wire sealing ring. The side of the main body of the detection area facing the second adapter plate is provided with an annular groove for accommodating the indium wire sealing ring, and the side of the second metal shielding box facing the second adapter plate is provided with an annular groove for accommodating the indium wire sealing ring.

[0020] In one embodiment of the present invention, a first square plate and a second square plate are further included. The first square plate and the second square plate are respectively installed on both sides of the detection area body. There are two first square plates. Two first reflectors are respectively installed on the two first square plates. The second reflector is installed on the second square plate.

[0021] The first square plate is located on the side close to the re-pumped transport light assembly, and the two first square plates correspond to the upper energy level probe light tube and the lower energy level probe light tube, respectively. The second square plate is located on the side close to the probe light assembly, and the second square plate corresponds to the re-pumped transport light tube.

[0022] The first adapter plate has a square groove on the side facing the main body of the detection area for accommodating the second square plate, and the second adapter plate has a square groove on the side facing the main body of the detection area for accommodating the first square plate.

[0023] In one embodiment of the present invention, the selective beam pushing assembly includes a third metal shielding box and a selective beam pushing mirror tube. The third metal shielding box is installed on the main body of the detection area, and the selective beam pushing mirror tube is located inside the third metal shielding box. A third cutoff waveguide is provided on the side of the third metal shielding box away from the main body of the detection area. An optical fiber is provided in the third cutoff waveguide, and the optical fiber in the third cutoff waveguide is connected to the selective beam pushing mirror tube.

[0024] In one embodiment of the present invention, the fluorescence collection assembly includes a fourth metal shielding box, an upper-level fluorescence collection lens tube, and a lower-level fluorescence collection lens tube. The fourth metal shielding box is installed on the main body of the detection region. The upper-level fluorescence collection lens tube and the lower-level fluorescence collection lens tube are both located inside the fourth metal shielding box. Two fourth cutoff waveguides are provided on the side of the fourth metal shielding box away from the main body of the detection region. Each fourth cutoff waveguide is provided with a signal transmission line. The signal transmission lines in the two fourth cutoff waveguides are respectively connected to the upper-level fluorescence collection lens tube and the lower-level fluorescence collection lens tube.

[0025] In one embodiment of the present invention, the axis of the upper level fluorescence collection lens tube and the axis of the upper level probe light lens tube are located on the same plane, the axis of the lower level fluorescence collection lens tube and the axis of the lower level probe light lens tube are located on the same plane, and the axis of the selected state push light lens tube and the axis of the re-pump light lens tube are located on the same plane.

[0026] In one embodiment of the present invention, at least one of the first metal shielding box, the second metal shielding box, the third metal shielding box and the fourth metal shielding box is made of a non-magnetic material.

[0027] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0028] In the above-described scheme of this application, the cold atom clock optical detection device includes a detection region body and a detection light assembly, a re-pump light assembly, a selective push light assembly, and a fluorescence collection assembly mounted on the detection region body. The detection region body has an internal chamber, and its upper surface has a perforation for passing through the cold atom cluster, which communicates with the chamber. The detection light assembly, the selective push light assembly, the re-pump light assembly, and the fluorescence collection assembly are arranged sequentially along the circumference of the detection region body, with the detection light assembly and the re-pump light assembly facing each other, and the selective push light assembly and the fluorescence collection assembly facing each other. The detection light assembly includes a first gold... The detector comprises a shielding box, an upper-level probe light tube, and a lower-level probe light tube. The first metal shielding box is installed on the main body of the detection area. Both the upper-level and lower-level probe light tubes are located inside the first metal shielding box. Two first cutoff waveguides are provided on the side of the first metal shielding box away from the main body of the detection area. Each first cutoff waveguide contains an optical fiber, and the optical fibers in the two first cutoff waveguides are respectively connected to the upper-level and lower-level probe light tubes. Two first reflectors are provided inside the main body of the detection area, and the two first reflectors correspond to the upper-level and lower-level probe light tubes respectively. With this structure, the first metal shielding box can use the high conductivity of metal to shield GHz microwaves from entering the interior of the detection area through the lens tube. The first cutoff waveguide can effectively attenuate microwaves of the corresponding frequency, preventing them from entering the interior of the detection area. Through the combined action of the first metal shielding box and the first cutoff waveguide, external microwaves can be blocked from entering the interior of the detection area, passively eliminating the impact of microwave leakage on cold atom clock detection. Compared with traditional microwave interference switches, microwave frequency shifting, and other schemes, the device described in this application has a simple structure, strong environmental adaptability, and is conducive to industrial development.

[0029] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0030] Figure 1 This is a three-dimensional schematic diagram of the optical detection device in an embodiment of the present invention;

[0031] Figure 2 This is a schematic diagram of the main body of the detection area in an embodiment of the present invention;

[0032] Figure 3 This is a cross-sectional view of the optical detection device along the axis of the re-pumped optical mirror tube in an embodiment of the present invention;

[0033] Figure 4 This is a cross-sectional view of the optical detection device along the axis of the selected state pushing mirror tube in an embodiment of the present invention;

[0034] Figure 5 This is a schematic diagram of the optical detection device removing the first metal shielding box in an embodiment of the present invention;

[0035] Figure 6 This is a cross-sectional view of the light detection device in an embodiment of the present invention. Figure 1 ;

[0036] Figure 7 This is a cross-sectional view of the light detection device in an embodiment of the present invention. Figure 2 ;

[0037] Figure 8 This is a cross-sectional view of the light detection device in an embodiment of the present invention. Figure 3 ;

[0038] Figure 9 This is a cross-sectional view of the light detection device in an embodiment of the present invention. Figure 4 ;

[0039] Figure 10 This is a schematic diagram of the first adapter plate in an embodiment of the present invention;

[0040] Figure 11 This is a schematic diagram of the second adapter plate in an embodiment of the present invention;

[0041] Figure 12 This is a schematic diagram of the first metal shielding box in an embodiment of the present invention;

[0042] Figure 13 This is a schematic diagram of the second metal shielding box in an embodiment of the present invention;

[0043] Figure 14 This is a schematic diagram of the third metal shielding box in an embodiment of the present invention;

[0044] Figure 15 This is a schematic diagram of the fourth metal shielding box in an embodiment of the present invention.

[0045] Reference numerals: 1-Detector body, 101-Upper flange, 102-Lower flange, 2-Detector light assembly, 201-First metal shielding box, 202-Upper energy level detector light tube, 203-Lower energy level detector light tube, 204-First cutoff waveguide, 3-Repump light assembly, 301-Second metal shielding box, 302-Repump light tube, 303-Second cutoff waveguide, 4-Selective push light assembly, 401-Third metal shielding box, 402-Selective push light tube, 403-Third cutoff waveguide, 5-Fluorescence collection assembly, 501-Fourth metal shielding box, 502-Upper energy level fluorescence collection tube, 503-Lower energy level fluorescence collection tube, 504-Fourth cutoff waveguide, 6-First reflector, 7-Second reflector, 8-First adapter plate, 9-Second adapter plate, 10-First square plate. Detailed Implementation

[0046] The present invention will be further described in detail below with reference to specific embodiments, but the implementation of the present invention is not limited thereto.

[0047] Please see Figures 1 to 15 This invention provides a cold atom clock optical detection device for eliminating the influence of microwave leakage. It includes a detection area body 1 and a detection optical component 2, a re-pump optical component 3, a selective push optical component 4, and a fluorescence collection component 5 mounted on the detection area body 1. The detection area body 1 has an internal cavity, and its upper surface has a perforation for passing through the cold atom cluster, which communicates with the cavity. The detection optical component 2, the selective push optical component 4, the re-pump optical component 3, and the fluorescence collection component 5 are arranged sequentially along the circumference of the detection area body 1. The detection optical component 2 and the re-pump optical component 3 are arranged opposite each other, and the selective push optical component 4 and the fluorescence collection component 5 are arranged opposite each other. The detection optical component 2 includes a first metal shielding box 201 and an upper energy... The upper-level probe light tube 202 and the lower-level probe light tube 203 are mounted on the main body 1 of the detection area. The upper-level probe light tube 202 and the lower-level probe light tube 203 are both located inside the first metal shielding box 201. Two first cutoff waveguides 204 are provided on the side of the first metal shielding box 201 away from the main body 1 of the detection area. Each first cutoff waveguide 204 contains an optical fiber. The optical fibers in the two first cutoff waveguides 204 are respectively connected to the upper-level probe light tube 202 and the lower-level probe light tube 203. Two first reflectors 6 are provided in the main body 1 of the detection area. The two first reflectors 6 correspond to the upper-level probe light tube 202 and the lower-level probe light tube 203 respectively.

[0048] In some embodiments of this application, such as Figure 1 , Figure 2 , Figure 3 and Figure 4 As shown, the detection zone body 1 includes a main body, an upper flange 101 and a lower flange 102. The upper flange 101 and the lower flange 102 are respectively installed on the upper and lower sides of the main body. The main body is a quadrangular prism structure. The four sides of the quadrangular prism structure are provided with four holes. A cavity is provided inside the main body. The upper flange 101, the main body and the lower flange 102 are provided with perforations for cold atom clusters to pass through.

[0049] In some embodiments of this application, the first metal shielding box 201 completely encloses the upper energy level probe light tube 202 and the lower energy level probe light tube 203. The first cutoff waveguide 204 is a cylindrical cutoff waveguide. The first cutoff waveguide 204 has a strong attenuation effect on stray microwaves in space. When the laser enters the probe light tube through the polarization-maintaining fiber, the polarization-maintaining fiber is connected to the corresponding probe light tube through a cylindrical cutoff waveguide. The stray microwaves cannot enter the probe light component 2 through the cutoff waveguide, and therefore cannot enter the probe area body 1 through the probe light component 2.

[0050] In some embodiments of this application, the function of the upper energy level probe light tube 202 and the lower energy level probe light tube 203 is to collimate the light output from the optical fiber into parallel light.

[0051] In some embodiments of this application, such as Figure 1 , Figure 3 and Figure 12 As shown, the function of the first metal shielding box 201 is to use the high electrical conductivity of the metal to shield GHz microwaves from entering the detection area through the lens tube. The circular cutoff waveguide on the first metal shielding box 201 facilitates the connection between the optical fiber and the lens tube. The inner diameter and length of the circular cutoff waveguide can effectively attenuate microwaves of the corresponding frequency, preventing them from entering the detection area.

[0052] In some embodiments of this application, the two first reflectors 6 correspond to the upper energy level probe light tube 202 and the lower energy level probe light tube 203, respectively. The function of the first reflectors 6 is to reflect the laser emitted from the tube back along the original path as much as possible to form a detection standing wave light.

[0053] In some embodiments of this application, atoms emit fluorescence into space after interacting with the detector standing wave light, similar to spherical light waves. At this time, a fluorescence collection component 5 is placed in the glass window of the detection area, allowing a portion of the fluorescence to be focused onto the photodetector through a lens group in the lens tube, forming a voltage signal. This signal is transmitted to an external acquisition device via a signal line. These voltage signals represent the number of atoms at each energy level, and through processing, they can reflect the frequency discrimination signal information required by the atomic clock. In other words, the function of the fluorescence collection component 5 is to convert the light signal reflecting the number of atoms after the interaction between atoms and the detector light into an electrical signal for acquisition by the acquisition device.

[0054] In some embodiments of this application, the repumping light component 3 is used to emit repumping light, which is typically used to pump atoms from a lower energy level to an upper energy level for photodetection, thus improving detection efficiency.

[0055] In the above-described scheme of this application, the cold atom clock optical detection device includes a detection area body 1 and a detection light component 2, a re-pump light component 3, a state-selection push light component 4, and a fluorescence collection component 5 installed on the detection area body 1. The detection area body 1 has a cavity inside, and the upper surface of the detection area body 1 has a perforation for passing through the cold atom cluster, which communicates with the cavity. The detection light component 2, the state-selection push light component 4, the re-pump light component 3, and the fluorescence collection component 5 are arranged sequentially along the circumference of the detection area body 1. The detection light component 2 and the re-pump light component 3 are arranged opposite each other, and the state-selection push light component 4 and the fluorescence collection component 5 are arranged opposite each other. The detection light component 2 includes a first metal shielding box 201 and an upper energy level detection light tube. 202. The lower energy level probe optical tube 203 and the first metal shielding box 201 are installed on the main body 1 of the detection area. The upper energy level probe optical tube 202 and the lower energy level probe optical tube 203 are both located inside the first metal shielding box 201. Two first cutoff waveguides 204 are provided on the side of the first metal shielding box 201 away from the main body 1 of the detection area. Each first cutoff waveguide 204 contains an optical fiber. The optical fibers in the two first cutoff waveguides 204 are respectively connected to the upper energy level probe optical tube 202 and the lower energy level probe optical tube 203. Two first reflectors 6 are provided in the main body 1 of the detection area. The two first reflectors 6 correspond to the upper energy level probe optical tube 202 and the lower energy level probe optical tube 203 respectively. With this structure, the first metal shielding box 201 can use the high conductivity of metal to shield GHz microwaves from entering the interior of the detection area 1 through the lens tube. The first cutoff waveguide 204 can effectively attenuate microwaves of the corresponding frequency, preventing them from entering the interior of the detection area 1. Through the combined action of the first metal shielding box 201 and the first cutoff waveguide 204, external microwaves can be blocked from entering the interior of the detection area 1, passively eliminating the impact of microwave leakage on cold atom clock detection. Compared with traditional microwave interference switches, microwave frequency shifting, and other schemes, the device described in this application has a simple structure, strong environmental adaptability, and is conducive to industrial development.

[0056] In some embodiments of this application, such as Figure 1 , Figure 3 , Figure 5 , Figure 6 , Figure 7 , Figure 8 , Figure 9 , Figure 13As shown, the repumping optical assembly 3 includes a second metal shielding box 301 and a repumping optical mirror tube 302. The second metal shielding box 301 is mounted on the detection area body 1, and the repumping optical mirror tube 302 is located inside the second metal shielding box 301. A second cutoff waveguide 303 is provided on the side of the second metal shielding box 301 away from the detection area body 1. An optical fiber is installed inside the second cutoff waveguide 303 and is connected to the repumping optical mirror tube 302. A second reflector 7 is provided inside the detection area body 1, corresponding to the repumping optical mirror tube 302. With this structure, through the combined action of the second metal shielding box 301 and the second cutoff waveguide 303, external microwaves can be blocked from entering the interior of the detection area body 1 through the repumping optical assembly 3, eliminating the influence of microwave leakage on the cold atom clock detection. The second reflector 7 in the detection area can form a precise standing wave optical field, ensuring efficient atomic state pumping. The aforementioned structure requires no active adjustment and boasts advantages such as simple structure, strong environmental adaptability, and high reliability. It improves the accuracy and stability of cold atom clocks, providing key technological support for industrial applications. The method by which the re-pumping transport beam tube 302 shields stray microwaves and forms a standing wave optical field is consistent with that of the probe beam tube.

[0057] In some embodiments of this application, such as Figure 1 , Figure 3 , Figure 5 , Figure 6 , Figure 7 , Figure 8 and Figure 9 As shown, the optical axes of the upper-level probe light tube 202, the lower-level probe light tube 203, and the re-pumped transport light tube 302 are parallel to each other, and the optical axis of the re-pumped transport light tube 302 is located between the optical axes of the upper-level probe light tube 202 and the lower-level probe light tube 203; the first reflector 6 is located on the side close to the re-pumped light component 3, and the two first reflectors 6 are coaxially arranged with the upper-level probe light tube 202 and the lower-level probe light tube 203 respectively; the second reflector 7 is located on the side close to the probe light component 2, and the second reflector 7 is coaxially arranged with the re-pumped transport light tube 302. This parallel coaxial optical structure, with the upper-level probe beam, lower-level probe beam, and repump beam arranged in parallel axes, ensures precise intersection of the probe and repump beams along the atom's falling path, significantly improving atomic state detection efficiency. The coaxial mirror configuration creates ideal standing-wave fields for each beam, significantly enhancing the interaction intensity between light and atoms. The symmetrical optical structure simplifies the optical path calibration process and reduces system assembly complexity, while the compact layout effectively saves space while maintaining the independence of each beam. This structure ensures accurate timing control through precise control of the optical path difference, achieving optimal optical performance and system reliability while maintaining excellent microwave shielding performance, providing crucial assurance for the high-precision operation of cold atom clocks.

[0058] In some embodiments of this application, such as Figure 1 , Figure 3 and Figure 10 As shown, the cold atom clock optical detection device also includes a first adapter plate 8, which is detachably connected to the detection area body 1, and a first metal shielding box 201 is detachably connected to the first adapter plate 8. An indium wire sealing ring is provided between the first adapter plate 8 and the detection area body 1, and between the first adapter plate 8 and the first metal shielding box 201. The first adapter plate 8 has two first through holes, corresponding to the upper energy level detector light tube 202 and the lower energy level detector light tube 203, respectively. Both sides of the first adapter plate 8 have annular grooves for accommodating the indium wire sealing rings. The detection area body 1 has an annular groove on the side facing the first adapter plate 8, and the first metal shielding box 201 has an annular groove on the side facing the first adapter plate 8. This structure facilitates maintenance and replacement through modular connections between the adapter plate, the detection area body 1, and the metal shielding box, while ensuring microwave shielding at each interface through the indium wire sealing rings in the annular grooves. The dual-through-hole structure precisely aligns with the upper and lower energy level probe light tubes 203, ensuring optical path collimation. The multi-layered indium wire sealing structure effectively blocks microwave leakage while also ensuring ease of assembly and long-term reliability, providing crucial support for the stable operation of the cold atom clock. This structure not only meets the stringent sealing requirements of precision instruments but also improves the maintainability and environmental adaptability of the equipment.

[0059] In some embodiments of this application, the first metal shielding box 201 is fixed to the first adapter plate 8 with screws, and the other side of the first adapter plate 8 is fixed to the detection area body 1 with screws.

[0060] In some embodiments of this application, such as Figure 1 , Figure 3 and Figure 11As shown, the cold atom clock optical detection device also includes a second adapter plate 9, which is detachably connected to the detection area body 1. A second metal shielding box 301 is also detachably connected to the second adapter plate 9. An indium wire sealing ring is provided between the second adapter plate 9 and the detection area body 1, and between the second adapter plate 9 and the second metal shielding box 301. The second adapter plate 9 has a second through hole corresponding to the re-pumped transport lens tube 302. Both sides of the second adapter plate 9 have annular grooves for accommodating the indium wire sealing rings. The detection area body 1 has an annular groove on the side facing the second adapter plate 9, and the second metal shielding box 301 has an annular groove on the side facing the second adapter plate 9. With this structure, the second adapter plate 9 is detachably connected to the detection area body 1 and the second metal shielding box 301, with three indium wire sealing rings respectively located on both sides of the adapter plate and between the connecting components. The second adapter plate 9 features precisely aligned through holes to ensure the optical path is aligned during re-extraction, and the annular grooves on each connecting surface ensure a secure installation of the indium wire sealing ring. This structure effectively blocks microwave leakage, ensuring both the electromagnetic shielding requirements of the detection device and facilitating routine maintenance. Standardized connection methods between components improve assembly accuracy and system reliability.

[0061] In some embodiments of this application, such as Figure 6 , Figure 7 , Figure 8 and Figure 9 As shown, the cold atom clock optical detection device also includes a first square plate 10 and a second square plate. The first square plate 10 and the second square plate are respectively installed on both sides of the detection area body 1. There are two first square plates 10, and two first reflectors 6 are respectively installed on the two first square plates 10. The second reflector 7 is installed on the second square plate. The first square plate 10 is located on the side closer to the re-pumped optical component 3, and the two first square plates 10 correspond to the upper energy level detector optical tube 202 and the lower energy level detector optical tube 203, respectively. The second square plate is located on the side closer to the detector optical component 2, and the second square plate corresponds to the re-pumped optical tube 302. The first adapter plate 8 has a square groove on the side of the detection area body 1 to accommodate the second square plate, and the second adapter plate 9 has a square groove on the side of the detection area body 1 to accommodate the first square plate 10. With this structure, the two first square plates 10 and the second square plate fix the reflectors respectively, and are precisely positioned with the adapter plate through the square grooves. The first square plate 10 corresponds to the upper and lower energy level probe light tubes 203, and the second square plate aligns with the re-pump light tube 302, ensuring that each reflector is strictly coaxial with the optical path. The square groove structure on the adapter plate ensures stable installation of the square plate and precise adjustment of the reflector position. This modular structure simplifies the assembly process while ensuring the collimation accuracy of the optical path, facilitates quick positioning during maintenance, and the mechanical cooperation between the components ensures both the positioning accuracy of the reflectors and maintains the overall rigidity of the system.

[0062] In some embodiments of this application, such as Figure 4 , Figure 5 and Figure 14 As shown, the selective beam pushing assembly 4 includes a third metal shielding box 401 and a selective beam pushing mirror tube 402. The third metal shielding box 401 is installed on the main body 1 of the detection area, and the selective beam pushing mirror tube 402 is located inside the third metal shielding box 401. A third cutoff waveguide 403 is provided on the side of the third metal shielding box 401 away from the main body 1 of the detection area. An optical fiber is installed inside the third cutoff waveguide 403, and the optical fiber inside the third cutoff waveguide 403 is connected to the selective beam pushing mirror tube 402. With this structure, the selective beam pushing assembly 4 uses the third metal shielding box 401 to wrap the mirror tube, combined with the third cutoff waveguide 403 to achieve microwave shielding. The metal box blocks external microwave interference, and the cutoff waveguide allows the optical fiber to transmit laser light while filtering out stray microwaves. This passive shielding structure does not require active adjustment and is simple and reliable. The direct connection between the selective beam pushing mirror tube 402 and the optical fiber ensures the optical path transmission efficiency, and the size of the cutoff waveguide is optimized for the working frequency band to ensure high-frequency microwave attenuation and avoid microwave leakage affecting the atomic state detection accuracy.

[0063] In some embodiments of this application, such as Figure 4 , Figure 5 and Figure 15 As shown, the selective beam pusher 402 primarily emits traveling wave light and does not require a reflector to return the emitted light along its original path. The selective beam pusher's function is to repel any remaining cold atoms that do not participate in the excitation cavity transitions. After emission, the selective beam pusher is perpendicular to the re-pump light, and their centers coincide at the center of the detection region, also located between the two detection beams. The selective beam pusher 402 shields stray microwaves and forms a standing wave field in the same way as the detection beam 402.

[0064] In some embodiments of this application, the fluorescence collection assembly 5 includes a fourth metal shielding box 501, an upper-level fluorescence collection lens tube 502, and a lower-level fluorescence collection lens tube 503. The fourth metal shielding box 501 is mounted on the detection area body 1. Both the upper-level fluorescence collection lens tube 502 and the lower-level fluorescence collection lens tube 503 are located inside the fourth metal shielding box 501. Two fourth cutoff waveguides 504 are provided on the side of the fourth metal shielding box 501 away from the detection area body 1. Each fourth cutoff waveguide 504 contains a signal transmission line, and the signal transmission lines in the two fourth cutoff waveguides 504 are respectively connected to the upper-level fluorescence collection lens tube 502 and the lower-level fluorescence collection lens tube 503. With this structure, the fourth metal box effectively shields external microwave interference, while the two independent fourth cutoff waveguides 504 selectively filter stray microwaves introduced by the signal transmission lines. The separate structure of the upper and lower level fluorescence collection lens tubes 503 ensures the energy level resolution detection accuracy, and each lens tube is equipped with a dedicated cutoff waveguide and signal channel to avoid signal crosstalk. The cutoff waveguide allows fluorescence signal transmission while simultaneously attenuating microwaves in the operating frequency band of the cold atom clock, thus blocking leakage paths.

[0065] In some embodiments of this application, two fluorescence collecting tubes collect two beams of detector standing wave light, which interact with atoms to form fluorescence. The fluorescence collecting tubes are fixed to an adapter plate with screws. One side of the adapter plate is fixed to a metal shielding box, and the other side is fixed to the detector body 1.

[0066] In some embodiments of this application, such as Figure 4 and Figure 5 As shown, the axis of the upper-level fluorescence collection tube 502 and the axis of the upper-level detector tube 202 are on the same plane; the axis of the lower-level fluorescence collection tube 503 and the axis of the lower-level detector tube 203 are on the same plane; and the axis of the state-selection pusher tube 402 and the axis of the re-pumper tube 302 are on the same plane. This coplanar optical path structure ensures that each functional beam precisely intersects on the atomic falling path. The coplanar arrangement of the upper and lower level fluorescence collection tubes 503 and their corresponding detector tubes ensures strict matching between the fluorescence detection region and the excitation light field, improving signal collection efficiency. The coplanar arrangement of the state-selection pusher and re-pumper beams ensures the spatiotemporal consistency of atomic state preparation and detection. The spatial arrangement of all optical axes is optimized based on atomic motion trajectories, avoiding signal loss due to optical path offset. The coplanar structure simplifies the optical path calibration process while maintaining the independence of each beam's action, ensuring the accuracy of energy level-resolved detection.

[0067] In some embodiments of this application, the fourth metal shielding box 501 completely encloses the upper and lower fluorescence collection devices. Only the signal line of the fluorescence collection lens passes through the upper and lower circular cutoff waveguides at the end of the metal shielding box away from the detection area and connects to the external signal acquisition device. The center of the upper fluorescence collection lens and the mounting center of the upper detector lens are on the same plane, and the center of the lower fluorescence collection lens and the mounting center of the lower detector lens are on the same plane.

[0068] In some embodiments of this application, at least one of the first metal shielding box 201, the second metal shielding box 301, the third metal shielding box 401, and the fourth metal shielding box 501 is made of a non-magnetic material to prevent the influence of magnetic materials on the detection area. When oxygen-free copper is selected, the indium wire sealing blade needs to be welded with a high-hardness material such as titanium.

[0069] In some embodiments of this application, the non-magnetic material can be oxygen-free copper, titanium, etc.

[0070] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0071] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0072] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0073] The above description, in conjunction with specific preferred embodiments, provides a further detailed explanation of the present invention. It should not be construed that the specific implementation of the present invention is limited to these descriptions. For those skilled in the art, various simple deductions or substitutions can be made without departing from the concept of the present invention, and all such modifications and substitutions should be considered within the scope of protection of the present invention.

Claims

1. A cold atomic clock light detection device that eliminates the effects of microwave leakage, characterized in that, The detection area main body is internally provided with a chamber, and an upper surface of the detection area main body is provided with a through hole for passing through a cold atom group, the through hole being in communication with the chamber; The detection light assembly, the state selection push light assembly, the heavy pumping light assembly and the fluorescence collection assembly are sequentially arranged along a circumferential direction of the detection area main body, the detection light assembly and the heavy pumping light assembly are oppositely arranged, and the state selection push light assembly and the fluorescence collection assembly are oppositely arranged; The detection light assembly comprises a first metal shielding box, an upper energy level detection light lens barrel and a lower energy level detection light lens barrel, the first metal shielding box is mounted on the detection area main body, the upper energy level detection light lens barrel and the lower energy level detection light lens barrel are located in the first metal shielding box, a side of the first metal shielding box away from the detection area main body is provided with two first cutoff waveguides, an optical fiber is arranged in each of the first cutoff waveguides, and the optical fibers in the two first cutoff waveguides are connected with the upper energy level detection light lens barrel and the lower energy level detection light lens barrel respectively; The detection area main body is internally provided with two first mirrors, and the two first mirrors correspond to the upper energy level detection light lens barrel and the lower energy level detection light lens barrel respectively; The heavy pumping light assembly comprises a second metal shielding box and a heavy pumping light lens barrel, the second metal shielding box is mounted on the detection area main body, the heavy pumping light lens barrel is located in the second metal shielding box, a side of the second metal shielding box away from the detection area main body is provided with a second cutoff waveguide, an optical fiber is arranged in the second cutoff waveguide, and the optical fiber in the second cutoff waveguide is connected with the heavy pumping light lens barrel; The detection area main body is internally provided with a second mirror, and the second mirror corresponds to the heavy pumping light lens barrel; The optical axis of the upper energy level detection light lens barrel, the optical axis of the lower energy level detection light lens barrel and the optical axis of the heavy pumping light lens barrel are parallel to each other, and the optical axis of the heavy pumping light lens barrel is located between the optical axis of the upper energy level detection light lens barrel and the optical axis of the lower energy level detection light lens barrel; The first mirrors are located on a side close to the heavy pumping light assembly, the two first mirrors are coaxially arranged with the upper energy level detection light lens barrel and the lower energy level detection light lens barrel respectively, the second mirror is located on a side close to the detection light assembly, and the second mirror is coaxially arranged with the heavy pumping light lens barrel.

2. The cold atomic clock optical detection apparatus to eliminate the influence of microwave leakage according to claim 1, characterized in that, The first adapter plate is detachably connected with the detection area main body, and the first metal shielding box is detachably connected with the first adapter plate. The first adapter plate and the detection area body are provided with an indium wire sealing ring, the first adapter plate and the first metal shielding box are provided with an indium wire sealing ring, the first adapter plate is provided with two first through holes, the two first through holes correspond to the upper energy level detection light lens barrel and the lower energy level detection light lens barrel respectively, the two side surfaces of the first adapter plate are provided with annular grooves for accommodating the indium wire sealing ring, one side of the detection area body facing the first adapter plate is provided with an annular groove for accommodating the indium wire sealing ring, and one side of the first metal shielding box facing the first adapter plate is provided with an annular groove for accommodating the indium wire sealing ring.

3. The cold atomic clock optical detection apparatus to eliminate the influence of microwave leakage according to claim 2, characterized in that, The second adapter plate is detachably connected with the detection area body, and the second metal shielding box is detachably connected with the second adapter plate. The second adapter plate and the detection area body are provided with an indium wire sealing ring, the second adapter plate and the second metal shielding box are provided with an indium wire sealing ring, the second adapter plate is provided with a second through hole, the second through hole corresponds to the heavy pumping light lens barrel, the two side surfaces of the second adapter plate are provided with annular grooves for accommodating the indium wire sealing ring, one side of the detection area body facing the second adapter plate is provided with an annular groove for accommodating the indium wire sealing ring, and one side of the second metal shielding box facing the second adapter plate is provided with an annular groove for accommodating the indium wire sealing ring.

4. The cold atomic clock optical detection apparatus to eliminate the influence of microwave leakage according to claim 3, characterized in that, The first square plate and the second square plate are respectively installed on the two sides of the detection area body, the first square plate is provided with two first reflecting mirrors, and the second reflecting mirror is installed on the second square plate. The first square plate is located on the side close to the heavy pumping light assembly, and the two first square plates correspond to the upper energy level detection light lens barrel and the lower energy level detection light lens barrel respectively, the second square plate is located on the side close to the detection light assembly, and the second square plate corresponds to the heavy pumping light lens barrel, The first adapter plate is provided with a square groove on one side surface facing the detection area body for accommodating the second square plate, and the second adapter plate is provided with a square groove on one side surface facing the detection area body for accommodating the first square plate.

5. The cold atomic clock optical detection apparatus to eliminate the effect of microwave leakage according to claim 1, wherein, The state selection light pushing assembly comprises a third metal shielding box and a state selection light pushing lens barrel, the third metal shielding box is installed on the detection area body, the state selection light pushing lens barrel is located in the third metal shielding box, the third metal shielding box is provided with a third cutoff waveguide away from the detection area body, an optical fiber is arranged in the third cutoff waveguide, and the optical fiber in the third cutoff waveguide is connected with the state selection light pushing lens barrel.

6. The cold atomic clock optical detection apparatus to eliminate the influence of microwave leakage according to claim 5, characterized in that, The fluorescence collection assembly comprises a fourth metal shielding box, an upper energy level fluorescence collection lens barrel and a lower energy level fluorescence collection lens barrel, the fourth metal shielding box is installed on the detection area main body, the upper energy level fluorescence collection lens barrel and the lower energy level fluorescence collection lens barrel are located in the fourth metal shielding box, two fourth cut-off waveguides are arranged on the side of the fourth metal shielding box away from the detection area main body, a signal transmission line is arranged in each fourth cut-off waveguide, and the signal transmission lines in the two fourth cut-off waveguides are connected with the upper energy level fluorescence collection lens barrel and the lower energy level fluorescence collection lens barrel respectively.

7. The cold atomic clock optical detection apparatus to eliminate the effect of microwave leakage according to claim 6, characterized in that, The axis of the upper energy level fluorescence collection lens barrel is located on the same plane as the axis of the upper energy level detection light lens barrel, the axis of the lower energy level fluorescence collection lens barrel is located on the same plane as the axis of the lower energy level detection light lens barrel, and the axis of the selected state light pushing lens barrel is located on the same plane as the axis of the heavy pumping light lens barrel.

8. The cold atomic clock optical detection apparatus to eliminate the influence of microwave leakage according to claim 6, characterized in that, The material of at least one of the first metal shielding box, the second metal shielding box, the third metal shielding box and the fourth metal shielding box is a non-magnetic material.

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