Magnetic selection state device and hydrogen atomic clock

Abstract

The present invention relates to the technical field of atomic clocks, and discloses a magnetic state selector device and a hydrogen atomic clock. The magnetic state selector device includes a housing, a plurality of magnetic poles, a plurality of magnets and a vacuum assembly. The housing has a cavity, and a plurality of card slots are arranged in the cavity. The plurality of card slots are evenly spaced along the circumferential direction of the cavity. The cavity has a through first end and a second end in the length direction of the housing. The first end is used for sealing connection with a hydrogen atom source, and the second end is used for sealing connection with an atomic storage cell. The plurality of magnetic poles are arranged in the card slots, and the tips of the plurality of magnetic poles all extend to the center line of the cavity. The plurality of magnets are arranged in the cavity, and any one magnetic pole is clamped between two adjacent magnets. The plurality of magnets enclose to form a magnetic field space, and the center line of the magnetic field space coincides with the center line of the cavity. The vacuum assembly is arranged outside the housing and is communicated with the cavity through a through hole on the housing. The vacuum assembly is used to enable the cavity to be in a vacuum environment.

Description

Technical Field

[0001] The present invention relates to the technical field of atomic clocks, and in particular to a magnetic state selector device and a hydrogen atomic clock. Background Art

[0002] The beam optical system of a hydrogen atomic clock includes a collimator, a magnetic state selector, and an atomic storage bubble port. In theory, the centers of the three need to be on the same optical line, which is the beam optical system of the hydrogen atomic clock. Among them, the assembly structure and process of the magnetic state selector are the most complex. The magnetic state selector is generally divided into a quadrupole magnetic state selector and a hexapole magnetic state selector. In the prior art, the quadrupole magnetic state selector includes magnetic poles, magnets, an upper top cover of the bracket, a lower top cover, and assembly screws. The assembly structure and process ultimately need to ensure that the distances between the four magnetic poles are the same and the upper, middle, and lower center points do not deviate from the physical center. After the assembled magnetic state selector is combined and assembled with the neck channel of the cylindrical cavity, it is ensured that the center points are still on the same optical line. The assembly difficulty is very high, the process difficulty is extremely high, and it is very difficult to ensure product consistency, so mass production cannot be achieved.

[0003] Therefore, there is an urgent need for a magnetic state selector device and a hydrogen atomic clock to solve the above problems. Summary of the Invention

[0004] An object of the present invention is to provide a magnetic state selector device, which can ensure the assembly process accuracy of the magnetic poles, reduce the assembly process difficulty, maintain the collimation of the beam optical system and the consistency of mass-produced products, and provide the possibility for the large-scale mass production of future hydrogen atomic clocks.

[0005] With the above concept, the technical solution adopted by the present invention is as follows:

[0006] Provide a magnetic state selector device, including;

[0007] A housing having a cavity therein, wherein a plurality of card slots are provided in the cavity, the bottoms of the plurality of card slots are located in the same plane and are evenly spaced along the circumferential direction of the cavity. The cavity has a through first end and a second end in the length direction of the housing. The first end is used for sealing connection with a hydrogen atom source, and the second end is used for sealing connection with an atomic storage bubble;

[0008] A plurality of magnetic poles are arranged in the card slots, and the tips of the plurality of magnetic poles all extend to the center line of the cavity;

[0009] A plurality of magnets are arranged in the cavity, and any one of the magnetic poles is clamped between two adjacent magnets. The plurality of magnets enclose a magnetic field space, and the center line of the magnetic field space coincides with the center line of the cavity;

[0010] A vacuum assembly is disposed outside the housing and communicated with the cavity through a through hole on the housing. The vacuum assembly is used to enable the cavity to be in a vacuum environment.

[0011] Optionally, an installation groove is provided at the tail end of the magnetic pole, and an installation protrusion is provided on the clamping groove. The tail end is inserted into the clamping groove, and the installation protrusion is inserted into the installation groove.

[0012] Optionally, the side wall of the installation groove close to the tail end has a guiding inclined surface, and there is a gap between the guiding inclined surface and the installation protrusion to facilitate the assembly of the magnetic pole. The side wall of the installation groove far from the tail end has an abutting surface, and the abutting surface abuts against the installation protrusion.

[0013] Optionally, the thickness of the magnetic pole is L1, and the depth of the installation groove is L2, where 0.1L1 ≤ L2 ≤ 0.2L1.

[0014] Optionally, a first flange is provided at the first end. A first sealing groove is provided around the cavity on the first flange. A first sealing member is provided in the first sealing groove. The first flange is detachably connected to the atomic storage cell, and the first sealing member is clamped between the first flange and the atomic storage cell.

[0015] Optionally, a second flange is provided at the second end. The second flange is communicated with the second end through an opening. A second sealing groove is provided around the opening on the second flange. A second sealing member is provided in the second sealing groove. The second flange is detachably connected to the hydrogen atom source, and the second sealing member is clamped between the second flange and the hydrogen atom source.

[0016] Optionally, the housing includes an outer shell and a fixing column. The outer shell has the cavity. The fixing column is provided on the bottom wall of the cavity and fits against the side wall of the cavity. The clamping groove is provided on the fixing column, and the clamping groove penetrates through the fixing column along the length direction of the outer shell.

[0017] Optionally, the magnet is made of samarium-cobalt alloy material;

[0018] The magnetic pole is made of pure iron material.

[0019] Optionally, perpendicular to the length direction of the housing, the cross-section of the cavity is square, circular or regular hexagon.

[0020] Another object of the present invention is to provide a hydrogen atomic clock, in which the magnetic pole assembly of the magnetic state selector device is simple, and the assembly process precision of the magnetic pole can be guaranteed. The collimation of the beam optical system and the consistency of mass-produced products can be maintained, providing the possibility for the large-scale mass production of hydrogen atomic clocks in the future.

[0021] As conceived above, the technical solution adopted by the present invention is:

[0022] A hydrogen atomic clock is provided, comprising the above-mentioned magnetic state selector device.

[0023] The beneficial effects of the present invention are:

[0024] The magnetic selector device proposed by the present invention includes a shell, a plurality of magnetic poles and a plurality of magnets. The shell has a cavity, a plurality of slots are arranged in the cavity, and the plurality of slots are evenly spaced along the circumference of the cavity. The plurality of magnetic poles are arranged in the slots, and the tips of the plurality of magnetic poles extend to the center line of the cavity. The plurality of magnets are arranged in the cavity, and any one of the magnetic poles is sandwiched between two adjacent magnets. The plurality of magnets are arranged to form a magnetic field space, and the center line of the magnetic field space coincides with the center line of the cavity. The cavity of the magnetic selector device has a first end and a second end that are connected in the length direction of the shell, and the first end is used for sealing connection with a hydrogen atom source, and the second end is used for sealing connection with an atom storage bubble. The magnetic selector device also includes a vacuum component, and the vacuum component is arranged outside the shell and communicated with the cavity through a through hole on the shell, and the vacuum component is used to enable the cavity to be in a vacuum environment. That is, the cavity of the magnetic selector device is a vacuum cavity, and the magnet and the magnetic pole are directly arranged in the vacuum cavity, which can avoid the problem that the coaxiality of the magnetic selector device and the vacuum cavity is difficult to ensure when the vacuum cavity is set separately. In addition, fixing the magnetic poles through the slots in the cavity can also avoid the problem of center point deviation that is easy to occur when assembling multiple magnetic poles. It can not only ensure the accuracy of the magnetic pole assembly process, but also reduce the difficulty of the assembly process, maintain the collimation of the beam optical system and the consistency of mass-produced products, and provide possibilities for large-scale mass production of hydrogen atomic clocks in the future.

[0025] The hydrogen atomic clock proposed in the present invention includes the above-mentioned magnetic selector device, and the magnetic poles of the magnetic selector device are easy to assemble, and the assembly process accuracy of the magnetic poles can be guaranteed, the collimation of the beam optical system and the consistency of mass-produced products can be maintained, and the possibility of large-scale mass production of hydrogen atomic clocks in the future is provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 is a partial structural schematic diagram of a magnetic state selector device provided in an embodiment of the present invention;

[0027] Figure 2 is a schematic structural diagram of a housing provided by an embodiment of the present invention;

[0028] Figure 3 is a cross-sectional view of a housing provided by an embodiment of the present invention;

[0029] Figure 4 It is a schematic diagram of the structure of the magnetic pole provided by an embodiment of the present invention.

[0030] In the figure:

[0031] 1. Housing; 11. Outer shell; 111. Cavity; 12. Fixed column; 121. Card slot; 1211. Mounting protrusion; 13. First flange; 131. First sealing groove; 14. Second flange; 140. Opening;

[0032] 2. Magnetic pole; 21. Tip; 22. Tail end; 221. Mounting groove; 2211. Guide slope;

[0033] 3. Magnet. Specific embodiments

[0034] To make the technical problems solved by the present invention, the technical solutions adopted and the achieved technical effects clearer, the technical solutions of the present invention will be further described below with reference to the accompanying drawings and through specific embodiments. It can be understood that the specific embodiments described herein are only used to explain the present invention, rather than limiting the present invention. In addition, it should be noted that for the convenience of description, only the parts related to the present invention are shown in the drawings, rather than all of them.

[0035] In the description of the present invention, unless otherwise clearly defined and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0036] In the present invention, unless otherwise clearly defined and limited, the first feature being "above" or "below" the second feature may include the direct contact between the first and second features, or may include the situation where the first and second features are not in direct contact but in contact through other features between them. Moreover, the first feature being "above", "above", and "on" the second feature includes the first feature being directly above and obliquely above the second feature, or simply indicating that the first feature is at a higher horizontal height than the second feature. The first feature being "below", "below", and "under" the second feature includes the first feature being directly below and obliquely below the second feature, or simply indicating that the first feature is at a lower horizontal height than the second feature.

[0037] In the description of this embodiment, the orientation or positional relationship such as "above", "below", "left", and "right" is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of description and simplifying the operation, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be understood as a limitation to the present invention. In addition, the terms "first" and "second" are only used for distinction in description and do not have special meanings.

[0038] The technical solution of the present invention will be further described below in conjunction with the accompanying drawings and through specific embodiments.

[0039] As Figures 1 to 4 shown, this embodiment provides a magnetic state selector device including a housing 1, a plurality of magnetic poles 2 and a plurality of magnets 3. The housing 1 has a cavity 111. A plurality of card slots 121 are provided in the cavity 111. The plurality of card slots 121 are evenly spaced along the circumference of the cavity 111. The plurality of magnetic poles 2 are arranged in the card slots 121, and the tips 21 of the plurality of magnetic poles 2 all extend to the center line of the cavity 111. The plurality of magnets 3 are arranged in the cavity 111, and any one magnetic pole 2 is clamped between two adjacent magnets 3. The plurality of magnets 3 enclose to form a magnetic field space. The center line of the magnetic field space coincides with the center line of the cavity 111, that is, the center points of the magnetic pole assembly composed of the plurality of magnetic poles 2 and the center points of the magnet assembly composed of the plurality of magnets 3 are on the same line. The cavity 111 of the magnetic state selector device has a through first end and a second end in the length direction of the housing 1. The first end is used for sealed connection with a hydrogen atom source, and the second end is used for sealed connection with an atomic storage bubble. The hydrogen atoms provided by the hydrogen atom source can enter the cavity 111 of the magnetic state selector device through the first end, and after being screened through the magnetic field space, finally enter the atomic storage bubble through the second end. The magnetic state selector device provided in this embodiment further includes a vacuum assembly. The vacuum assembly is arranged outside the housing 1 and communicates with the cavity 111 through a through hole on the housing 1. The vacuum assembly is used to enable the cavity 111 to be in a vacuum environment. That is, the cavity 111 of the magnetic state selector device is a vacuum chamber, and the magnet assembly and the magnetic pole assembly are directly arranged in the vacuum chamber, which can avoid the problem that it is difficult to ensure the coaxiality of the assembly of the magnetic state selector device and the vacuum chamber when a separate vacuum chamber is provided. In addition, fixing the magnetic poles 2 through the card slots 121 in the cavity 111 can also avoid the problem that the center points of the magnetic pole assembly are prone to deviation when assembling a plurality of magnetic poles 2. It can not only ensure the assembly process accuracy of the magnetic poles 2, but also reduce the assembly process difficulty, maintain the collimation of the beam optical system and the consistency of mass-produced products, and provide the possibility for the large-scale mass production of future hydrogen atomic clocks.

[0040] In specific implementation, the magnetic state selector device can be a quadrupole magnetic state selector device or a hexapole magnetic state selector device, and the corresponding card slots 121 can be four or six evenly spaced ones. Two of the four or six magnetic poles 2 form a pair, the tips 21 of each pair of magnetic poles 2 face each other and both face the center point, and any one magnetic pole 2 is clamped between two magnets 3 arranged at intervals. The magnetism of the magnets 3 on both sides of the magnetic pole 2 can fix the magnetic pole 2 in the card slot 121. During actual assembly, the magnetic pole 2 can be first inserted into the card slot 121. Since the magnetic pole 2 has no magnetism at this time, the magnetic pole 2 can be freely inserted into or removed from the card slot 121, and then a plurality of magnets 3 are respectively placed in the gaps between two adjacent magnetic poles 2. The two ends of two adjacent magnets 3 close to each other have opposite magnetisms to clamp the magnetic pole 2 between the two magnets 3. In addition, when the magnet 3 contacts the magnetic pole 2, the magnetism of the magnet 3 can be conducted to the magnetic pole 2. The magnetisms of the tips 21 of two opposite magnetic poles 2 are the same, and the repulsive force of the same magnetism makes the two opposite magnetic poles 2 both have a tendency to move away from each other, so that the magnetic pole 2 is pressed in the card slot 121 by the repulsive force between them.

[0041] Optionally, in the direction perpendicular to the length of the housing 1, the cross-section of the cavity 111 is square, circular or regular hexagon. The square is adapted to the quadrupole magnetic state selector device, the regular hexagon is adapted to the hexapole magnetic state selector device, and the circular shape is adapted to both the quadrupole magnetic state selector device and the hexapole magnetic state selector device.

[0042] In this embodiment, the material of the magnet 3 is samarium cobalt alloy, and the material of the magnetic pole 2 is pure iron. In this embodiment, four magnetic poles 2 are provided, and the pole centers of the four magnetic poles 2, that is, the tips 21, face each other. The four magnetic poles 2 can generate a gradient magnetic field, and the magnetic field intensity is symmetrically distributed in a quadrupole manner in space. When the substance to be selected (hydrogen atom) enters the cavity 111, due to the magnetic field action generated by the four magnetic poles 2, hydrogen atoms in different spin states have different magnetic moments, and the forces they receive in the magnetic field are also different. Substances with stronger magnetism will be subjected to greater attraction and move towards the direction of the magnetic pole 2, while substances with weaker magnetism or no magnetism will be subjected to smaller forces or almost no force, thereby realizing the magnetic separation of substances. This state selection mechanism is crucial for improving the medium- and long-term frequency stability of the hydrogen atomic clock, because it reduces the influence of invalid atomic states on the clock transition, thereby improving the atomic transition spectral line quality and the overall performance of the machine.

[0043] In this embodiment, the housing 1 includes a housing shell 11 and fixing posts 12. The housing shell 11 has a cavity 111, and the fixing posts 12 are arranged on the bottom wall of the cavity 111 and are in contact with the side wall of the cavity 111. A clamping groove 121 is arranged on the fixing post 12, and the clamping groove 121 penetrates through the fixing post 12 along the length direction of the housing shell 11. Specifically, during implementation, in the length direction of the housing 1, the lengths of the fixing post 12, the clamping groove 121, the magnet 3, and the magnetic pole 2 are all the same, and are all less than the length of the cavity 111, that is, after the hydrogen atoms complete the state selection in the cavity 111, they need to pass through a certain flight distance before entering the atomic storage bubble.

[0044] Optionally, the magnetic pole 2 has a tail end 22 and a tip 21. The tail end 22 is inserted into the clamping groove 121, and the tip 21 faces the center point. To facilitate the assembly of the magnetic pole 2 into the clamping groove 121, an installation groove 221 is arranged on the tail end 22 of the magnetic pole 2, and an installation protrusion 1211 is arranged on the clamping groove 121. The tail end 22 is inserted into the clamping groove 121, and the installation protrusion 1211 is inserted into the installation groove 221. The installation protrusion 1211 is used to prevent the magnetic pole 2 from disengaging from the clamping groove 121. As Figure 4 shown, the installation grooves 221 are arranged on two opposite side surfaces of the tail end 22, and both of these two side surfaces are in contact with the inner side wall of the clamping groove 121, while the installation protrusion 1211 is arranged at the notch of the clamping groove 121, so that the clamping groove 121 becomes a reduced-opening groove, and the installation groove 221 is also used to avoid the installation protrusion 1211, so that along the through direction of the clamping groove 121, the magnetic pole 2 can be inserted into the clamping groove 121, and in the direction of the tip 21 of the magnetic pole 2, the magnetic pole 2 cannot disengage from the clamping groove 121. The setting of the installation protrusion 1211 further improves the installation position accuracy of the magnetic pole 2 in the clamping groove 121.

[0045] Optionally, the side wall of the installation groove 221 close to the tail end 22 has a guiding inclined surface 2211, and there is a gap between the guiding inclined surface 2211 and the installation protrusion 1211 to facilitate the assembly of the magnetic pole 2, while the side wall of the installation groove 221 far from the tail end 22 has an abutting surface, and the abutting surface abuts against the installation protrusion 1211. As described above, after the magnetic pole 2 is assembled into the clamping groove 121, due to the same magnetism of the two opposite magnetic poles 2, the abutting surface of the magnetic pole 2 always abuts against the installation protrusion 1211, thereby limiting the installation position of the magnetic pole 2, and the gap between the guiding inclined surface 2211 and the installation protrusion 1211 facilitates the insertion of the magnetic pole 2 into the clamping groove 121 or the removal of the magnetic pole 2 from the clamping groove 121 during the assembly of the magnetic pole 2.

[0046] Optionally, the thickness of the magnetic pole 2 is L1, and the depth of the installation groove 221 is L2, where 0.1L1 ≤ L2 ≤ 0.2L1. The setting of the installation groove 221 not only ensures the accuracy of the setting position of the magnetic pole 2, but also needs to avoid damaging the strength of the magnetic pole 2 to ensure the service life of the magnetic state selection device.

[0047] In this embodiment, the first end of the magnetic state selector device is connected to the atomic storage cell, and to ensure a vacuum environment inside the cavity 111, the first end is hermetically connected to the atomic storage cell. Optionally, a first flange 13 is provided at the first end. A first sealing groove 131 is provided around the cavity 111 on the first flange 13. A first sealing member is provided in the first sealing groove 131. The first flange 13 is detachably connected to the atomic storage cell, and the first sealing member is clamped between the first flange 13 and the atomic storage cell. In specific implementation, the first sealant is a sealing ring, and the sealing ring is accommodated in the first sealing groove 131. A plurality of mounting holes are provided on the first flange 13, and the plurality of mounting holes are evenly spaced along the circumferential direction of the first flange 13. Fasteners can be used to pass through the plurality of mounting holes and connect to the atomic storage cell.

[0048] In this embodiment, the second end of the magnetic state selector device is connected to the hydrogen atom source, and to ensure a vacuum environment inside the cavity 111, the second end is hermetically connected to the hydrogen atom source. Optionally, a second flange 14 is provided at the second end. The hydrogen atom source is hermetically connected to the second flange 14, so that the hydrogen atoms provided by the hydrogen atom source can enter the cavity 111 through the second flange 14. As Figure 3 shown, an opening 140 is provided on the second flange 14, and the hydrogen atom source is connected to the opening 140, so that the hydrogen atom source and the cavity 111 are hermetically connected through the opening 140. A second sealing groove is provided around the opening 140 on the second flange 14. A second sealing member is provided in the second sealing groove. The second flange 14 is detachably connected to the hydrogen atom source, and the second sealing member is clamped between the second flange 14 and the hydrogen atom source.

[0049] This embodiment also provides a hydrogen atomic clock, including the above-mentioned magnetic state selector device. The magnetic poles 2 of the magnetic state selector device of this hydrogen atomic clock are simply assembled, and the assembly process accuracy of the magnetic poles 2 can be ensured. The collimation of the beam optical system and the consistency of mass-produced products can be maintained, providing the possibility for the large-scale mass production of hydrogen atomic clocks in the future.

[0050] The above embodiments only illustrate the basic principles and characteristics of the present invention. The present invention is not limited by the above embodiments. Without departing from the spirit and scope of the present invention, there are various changes and modifications to the present invention, and these changes and modifications all fall within the scope of the present invention claimed. The scope of the present invention claimed is defined by the appended claims and their equivalents.

Claims

1. A magnetic state selector device, characterized in that, including; a housing (1), the housing (1) having a cavity (111), a plurality of card slots (121) being provided in the cavity (111), bottoms of the plurality of card slots (121) being located in the same plane and being evenly spaced along a circumference of the cavity (111), the cavity (111) having a first end and a second end that are through in a length direction of the housing (1), the first end being used for sealing connection with a hydrogen atom source, and the second end being used for sealing connection with an atomic storage bubble; a plurality of magnetic poles (2), being provided in the card slots (121), tips (21) of the plurality of magnetic poles (2) all extending to a center line of the cavity (111); a plurality of magnets (3), being provided in the cavity (111), and any one of the magnetic poles (2) being clamped between two adjacent magnets (3), the plurality of magnets (3) surrounding to form a magnetic field space, a center line of the magnetic field space coinciding with the center line of the cavity (111); a vacuum assembly, being provided outside the housing (1) and communicating with the cavity (111) through a through hole in the housing (1), the vacuum assembly being used for enabling the cavity (111) to be in a vacuum environment.

2. The magnetic state selector device according to claim 1, wherein, An installation groove (221) is provided on a tail end (22) of the magnetic pole (2), an installation protrusion (1211) is provided on the card slot (121), the tail end (22) is inserted into the card slot (121), and the installation protrusion (1211) is inserted into the installation groove (221).

3. The magnetic state selector device according to claim 2, characterized in that, A side wall of the installation groove (221) close to the tail end (22) has a guiding inclined surface (2211), the guiding inclined surface (2211) having a gap with the installation protrusion (1211) to facilitate assembly of the magnetic pole (2), a side wall of the installation groove (221) away from the tail end (22) has an abutting surface, and the abutting surface abuts against the installation protrusion (1211).

4. The magnetic state selector device according to claim 2, wherein, The magnetic pole (2) has a thickness of L1, the installation groove (221) has a depth of L2, and 0.1L1 ≤ L2 ≤ 0.2L1.

5. The magnetic selection state device according to claim 1, characterized in that The first end is provided with a first flange (13), a first sealing groove (131) is provided on the first flange (13) around the cavity (111), a first sealing member is provided in the first sealing groove (131), the first flange (13) is detachably connected to the atomic storage bubble, and the first sealing member is clamped between the first flange (13) and the atomic storage bubble.

6. The magnetic state selector device according to claim 1, characterized in that, The second end is provided with a second flange (14), the second flange (14) communicates with the second end through an opening (140), a second sealing groove is provided on the second flange (14) around the opening (140), a second sealing member is provided in the second sealing groove, the second flange (14) is detachably connected to the hydrogen atom source, and the second sealing member is clamped between the second flange (14) and the hydrogen atom source.

7. The magnetic state selector device according to claim 1, characterized in that, The housing (1) includes a housing shell (11) and fixing posts (12). The housing shell (11) has the cavity (111). The fixing posts (12) are arranged on the bottom wall of the cavity (111) and are in contact with the side wall of the cavity (111). The clamping grooves (121) are arranged on the fixing posts (12), and the clamping grooves (121) penetrate through the fixing posts (12) along the length direction of the housing shell (11).

8. The magnetic state selector device according to claim 1, characterized in that, The magnet (3) is made of samarium cobalt alloy material; The magnetic pole (2) is made of pure iron material.

9. The magnetic state selector device according to claim 1, characterized in that, Perpendicular to the length direction of the housing (1), the cross-section of the cavity (111) is square, circular or regular hexagon.

10. Hydrogen atomic clock, characterized in that, It includes the magnetic selection state device according to any one of claims 1 to 9.

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