An atomic release source

Abstract

The present invention relates to an atomic release source, comprising a housing, an atomic cell, a heater and an atomic block; the housing has opposite proximal and distal ends, and the distal end of the housing has an atomic release hole; the atomic cell includes a cell housing and a cell cover, the cell housing is installed inside the housing, the cell housing has an opening, the cell cover is detachably sealed on the opening and is pressed by external air pressure, when the external air pressure of the cell housing drops to a certain level, the cell cover falls off; the atomic block is arranged inside the cell housing; the heater is installed inside the housing and is located outside the cell housing for heating the atomic block inside the cell housing; the present invention solves the technical problem of continuously and controllably releasing elemental atoms in an ultra-high vacuum environment for a miniaturized atomic release source, improves the use safety and convenience of the atomic release source, and solves the risk of potential damage to internal devices.

Description

Technical Field

[0001] The invention relates to the technical field of cold atoms, in particular to an atom release source. Background Art

[0002] Cold atom technology is a technology that uses the change of atomic quantum states to study the physical properties of atoms and make precise measurements. It is used in many fields such as quantum communication, atomic clocks, atomic gravimeters, and quantum simulation. Atom release sources provide high-purity single atoms required for the cold atom device to work. Usually, the cold atom device needs to be in a temperature better than 10 -7 Pa ultra-high vacuum environment, and capture atomic gas dispersed in space from the background gas in the environment. This requires the atomic release source to have an ultra-low impurity gas release rate and a high atomic release capacity.

[0003] There are two common ways to realize the atomic release source. One is to prepare single-atom by electrochemical reduction of atomic compounds. The other is to provide atoms for the cold atom device by relying on saturated vapor of single-atom atoms.

[0004] The former method is usually made of a combination of atomic chromate and getter material. It has flexible physical dimensions and can achieve high-purity atoms. At the same time, the atomic release rate can be controlled by the current size, which is suitable for scientific research experimental devices. However, this method has low preparation costs, and the total amount of atoms is usually on the order of 10 mg. The internal components of the ultra-high vacuum system are complicated to replace, and it is not suitable for long-term continuous working scenarios. At the same time, the control current needs to reach more than 5A, and the magnetic field generated in the small system cannot be ignored. In the process of cold atom technology moving from scientific research to engineering practice, this type of atomic release source cannot meet the requirements.

[0005] The latter method is to seal the prepared single atoms in a glass pool. Then place the glass pool in a pipe connected to the ultra-high vacuum system. When the vacuum system is exhausted, use pliers to crush the glass pool from the outside to keep the pipe intact, so as to release the atoms in the vacuum system. This method is simple in principle and low in cost, and can provide a total amount of atoms in the order of 10g for the cold atom device. However, this method requires an external pipe for releasing the atoms, which is not conducive to the integrated design of the cold atom device, and there is a risk of internal glass fragments damaging the internal devices of the device. Summary of the invention

[0006] Based on the above description, the present invention provides an atomic release source to solve the technical problem of realizing a miniaturized atomic release source to continuously and controllably release single atoms in an ultra-high vacuum environment, improve the safety and convenience of using the atomic release source, and solve the risk of potential damage to internal devices.

[0007] The technical solution of the present invention to solve the above technical problems is as follows: An atomic release source, characterized in that it includes a housing, an atomic cell, a heater, and an atomic block;

[0008] The housing has opposite proximal and distal ends, and the distal end of the housing has an atomic release hole;

[0009] The atomic cell includes a cell housing and a cell cover. The cell housing is installed inside the housing. The cell housing has an opening, and the cell cover is detachably sealed on the opening and is pressed by external air pressure. When the external air pressure outside the cell housing drops to a certain level, the cell cover falls off;

[0010] The atomic block is arranged inside the cell housing;

[0011] The heater is installed inside the housing and is located outside the cell housing for heating the atomic block inside the cell housing.

[0012] Compared with the prior art, the technical solution of the present application has the following beneficial technical effects:

[0013] When the present application is in use, first, the internal air pressure of the cell housing is reduced in advance, and then the cell cover is placed on the opening of the cell housing. The cell cover is pressed by the external air pressure. Then, the entire atomic cell is installed inside the housing. After the atomic release source is installed in the cold atom device, the environment where it is located is evacuated. The external pressure of the atomic cell drops. When the external pressure is not sufficient to press the cell cover, the cell cover falls off. The atomic vapor formed by heating the atomic block by the heater diffuses from the atomic release hole into the ultra-high vacuum cavity of the cold atom device. In the present invention, the production process between components is simple. Compared with common single-element atomic release sources, it has a smaller volume, has the ability to control the atomic release rate, and is conducive to integrated design; it does not crush the atomic cell, does not generate glass fragments, and there is no risk of damaging the internal devices of the device. In addition, in the present invention, a single-element atomic assembly is used. Compared with the chromate release source of common atoms, it has the advantages of a large atomic mass, a long service life, and a small release magnetic field.

[0014] On the basis of the above technical solution, the present invention can be further improved as follows.

[0015] Furthermore, it further includes a connector, a vacuum flange, and a support column. The support column is installed between the housing and the vacuum flange, and the connector passes through the vacuum flange and is electrically connected to the heater.

[0016] Furthermore, the housing includes a first housing and a second housing. The second housing is installed on one side of the first housing close to the distal end. One end of the support column is connected to the first housing, and the atomic release hole is formed on the outer wall of the second housing close to the distal end.

[0017] Further, the connector is a Feedthrough connector, and the vacuum flange is a CF vacuum flange.

[0018] Further, the cell housing is made of a hollow glass tube. The proximal end of the hollow glass tube is sealed by melting, and its distal end is polished smoothly. The cell cover has a glass sheet structure, and the side of the cell cover close to the cell housing is polished smoothly.

[0019] Further, the surface flatness of the distal end of the hollow glass tube and the side of the cell cover close to the cell housing is not greater than 10 μm.

[0020] Further, the heater includes an electric heating wire wound around the outside of the cell housing. The two electrical connection ends of the electric heating wire extend out from the proximal end of the first housing and are electrically connected to the connector.

[0021] Further, the electric heating wire is wound in a twisted manner.

[0022] Further, a sealing ring is also included. The sealing ring is installed on the side of the vacuum flange close to the outer housing, and the knife edge of the vacuum flange is pressed into the sealing ring.

[0023] Further, the atomic block is a single isotope atom, a natural abundance atom, or a combination of multiple atoms. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 FIG. is a schematic structural diagram of an atomic release source of the present invention.

[0025] Figure 2 FIG. is an exploded decomposition structural diagram of an atomic release source of the present invention.

[0026] Figure 3 FIG. is an installation schematic diagram of an atomic release source of the present invention and an ultra-high vacuum system.

[0027] Figure 4 FIG. is a schematic diagram of the force direction on the cell cover during the installation process of the atomic cell.

[0028] Figure 5 FIG. is a schematic diagram of the force direction on the cell cover during the opening process of the atomic cell in the ultra-high vacuum system.

[0029] In the figure: outer housing 1, atomic cell 2, heater 3, atomic block 4, connector 5, vacuum flange 6, support column 7, cell housing 21, cell cover 22, Feedthrough connector 51, CF vacuum flange 61, sealing ring 62, first housing 11, second housing 12, electric heating wire 31, electrical connection end 32, ultra-high vacuum cavity 20. DETAILED DESCRIPTION OF THE INVENTION

[0030] To facilitate the understanding of this application, the following will provide a more comprehensive description of this application with reference to the relevant attached drawings. Embodiments of this application are shown in the drawings. However, this application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, these embodiments are provided to make the disclosure of this application more thorough and comprehensive.

[0031] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which this application belongs. The terms used in the specification of this application herein are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0032] It can be understood that spatial relationship terms such as "under", "below", "lower", "beneath", "above", "upper", etc. can be used herein to describe the relationship between one element or feature shown in the drawings and other elements or features. It should be understood that in addition to the orientation shown in the drawings, spatial relationship terms also include different orientations of the devices during use and operation. For example, if the device in the drawing is flipped, the element or feature described as "under other elements" or "beneath it" or "under it" will be oriented "above" other elements or features. Therefore, the exemplary terms "under" and "below" can include both the upper and lower orientations. In addition, the device can also include other orientations (such as rotating 90 degrees or other orientations), and the spatial descriptive terms used herein are accordingly interpreted.

[0033] It should be noted that when an element is considered to be "connected" to another element, it can be directly connected to the other element or connected to the other element through an intermediate element. In the following embodiments, "connection", if there is an electrical signal or data transfer between the connected circuits, modules, units, etc., should be understood as "electrical connection", "communication connection", etc.

[0034] As used herein, the singular forms "a", "an" and "the" may also include the plural forms unless the context clearly dictates otherwise. It should also be understood that the terms "comprise / include" or "have" etc. specify the presence of the stated features, wholes, steps, operations, components, parts or combinations thereof, but do not preclude the possibility of the presence or addition of one or more other features, wholes, steps, operations, components, parts or combinations thereof.

[0035] As Figure 1 and Figure 2 shown, an atomic release source is provided in an embodiment of this application, which includes a housing 1, an atomic cell 2, a heater 3, an atomic block 4, a connector 5, a vacuum flange 6 and a support column 7.

[0036] Among them, the outer shell 1 has opposite proximal and distal ends, and the distal end of the outer shell 1 has an atomic release hole.

[0037] In this embodiment, the outer shell 1 is a cylindrical shell structure, which serves as a housing for the atomic release source. For the outside of the entire atomic release source, it has a cavity inside. Among them, the proximal end refers to the end closer to the outside when the outer shell is installed on the cold atom device.

[0038] The atomic cell 2 includes a cell housing 21 and a cell cover 22. The cell housing 21 is installed inside the outer shell 1. The cell housing 21 has an opening, and the cell cover 22 is detachably sealed on the opening and is pressed tightly by external air pressure. When the external air pressure outside the cell housing 21 drops to a certain level, the cell cover 22 falls off.

[0039] The atomic block 4 is arranged inside the cell housing 21.

[0040] The heater 3 is installed inside the outer shell 1 and is located outside the cell housing 21, and is used to heat the atomic block 4 inside the cell housing 21.

[0041] The support column 7 is installed between the outer shell 1 and the vacuum flange 6. The support column 7 is a metal structural member with appropriate dimensions and strength, and is used to support the main structure of the atomic release source. In specific implementation, the number of support columns 7 can be designed according to actual usage. In this embodiment, the number of support columns 7 is three, and they are evenly distributed along the circumference of the outer shell. Preferably, it is designed to have M3 threads at both the upper and lower ends and a length of 26 mm.

[0042] The connector 5 passes through the vacuum flange 6 and is electrically connected to the heater 3.

[0043] Preferably, the connector 5 is a Feedthrough connector 51. Preferably, a standard Feedthrough connector applied to ultra-high vacuum is used, which can transmit direct current not less than 1 A. The vacuum flange 6 is a CF vacuum flange 61, preferably of the CF50 flange model; specifically, the Feedthrough connector 51 is a special connector that passes through the vacuum chamber wall and transmits direct current or radio frequency signals between the atmosphere and the vacuum, and is used to transmit the power supply of the atomic release source heater from the outside into the ultra-high vacuum system. The CF vacuum flange 61 is a vacuum flange suitable for an ultra-high vacuum environment better than 10- 8 Pa ultra-high vacuum environment. A typical installation method is as Figure 3 , and installation holes matching the CF vacuum flange 61 are designed on the ultra-high vacuum cavity 20 of the cold atom device. The atomic release source is installed on the ultra-high vacuum cavity 20 through the CF vacuum flange 61.

[0044] To ensure the sealing properties of the installation gap, the atomic release source also includes a sealing ring 62, which is installed on the side of the CF vacuum flange 61 close to the outer shell 1 and is located between the installation gap between the CF vacuum flange 61 and the ultra-high vacuum chamber 20, wherein the blade of the CF vacuum flange 3 is pressed into the sealing ring 62. Preferably, the sealing ring can be selected as a low-hardness copper ring.

[0045] In this embodiment, the shell 1 adopts a split structure, that is, the shell 1 includes a first shell 11 and a second shell 12, wherein the second shell 12 is installed on the side of the first shell 11 close to the far end, one end of the support column 7 is connected to the first shell 11, and the atomic release hole is formed on the outer wall of the second shell 12 close to the far end.

[0046] Specifically, the Feedthrough connector 51 passes through the CF vacuum flange 61 in a dedicated connection method. A mounting structure is reserved on the CF vacuum flange 61 to fix the support column 7, and the support column 7 is mechanically connected to the first shell 11 for support. The Feedthrough connector 51 is connected to the heater 3 for powering the heater 3, wherein the first shell 11 is made of metal material, preferably copper alloy material, for mounting the heater 3 and the atomic pool 2, and the second shell 12 is made of metal material, preferably copper alloy of the same material, and the two are connected by threaded fitting, and the surface of the second shell 12 near the far end is designed with a porous structure to ensure that the atomic vapor can diffuse into the ultra-high vacuum cavity.

[0047] The pool shell 21 is made of a hollow glass tube, preferably a quartz glass round tube with an inner diameter of 30 mm, an outer diameter of 40 mm, and a length of 75 mm. In some optional embodiments of the present application, both ends of the pool shell 21 can be polished and smooth, the pool cover 22 is a glass sheet structure, the side of the pool cover 22 close to the pool shell 22 is polished and smooth and both are butt-sealed with the pool shell 21. In other optional embodiments of the present application, the proximal end of the hollow glass tube is melt-sealed, and its distal end is polished and smooth. The pool cover 22 is a glass sheet structure, the side of the pool cover 22 close to the pool shell 22 is polished and smooth and both are butt-sealed with the pool shell 21. The present application is preferably the second embodiment.

[0048] The smoothness mentioned in the present application refers to a surface flatness better than 10 μm.

[0049] In an embodiment of the present application, the heater 3 includes a heating wire 31 wound around the outer side of the cell housing. Two electrical connection ends 32 of the heating wire 31 extend from the proximal end of the first housing 11 and are electrically connected to the Feedthrough connector 51. The heating wire 31 is wound around the outer wall of the atomic cell 2 in a twisted pair manner, used to heat the atomic mass 4, increase the saturated vapor pressure of the elemental atoms, and thus increase the release speed. At the same time, it can effectively avoid the magnetic field caused by the current coil. Specifically, the heating wire 31 is made of enameled wire with a diameter of 0.5 mm, wound around the atomic cell 2 after being twisted in a pair, with a designed resistance of 10 Ω. When a current of 1 A is applied, the heat generation can reach 10 W.

[0050] The atomic mass 4 mentioned in the present application is a collection of elemental atoms, which can be selected as single isotope atoms, natural abundance atoms or a combination of multiple atoms according to actual needs. In this embodiment, it is preferably elemental rubidium atoms.

[0051] To have a clearer, more complete understanding and recognition of the technical solution of the present application, the following describes the specific usage mode of the embodiment of the present application:

[0052] First, under the protection of inert gas with a pressure of one-half standard atmospheric pressure, use a tooling and indium wire to tightly seal the cell cover 22 and the cell housing 21 with the atomic mass 4 placed inside, and then take it out and place it in the atmospheric environment. At this time, since the internal pressure of the atomic cell is lower than the external pressure, the atomic cell cover 21 is subjected to an atmospheric pressure of about 70 N, and the atmospheric pressure will maintain the seal between the cell cover 22 and the cell housing 21. As Figure 4 shown, the whole atomic release source assembly is assembled onto the ultra-high vacuum cavity 20 of the cold atom device. Use a molecular pump and an ion pump to evacuate the ultra-high vacuum cavity 20 to below 10- 7 Pa. At this time, the cell cover 22 is subjected to an outward force of 70 N, so that the cell cover 22 and the cell housing 21 are separated. As Figure 5 shown, the release of atoms is realized. The separated atomic cell cover 11 is restricted by the first housing 11 and the second housing 12 and will not collide with other components of the vacuum system of the cold atom device and cause damage.

[0053] In the present invention, the production process between components is simple. Compared with common elemental atom release sources, it has a smaller volume, has the ability to control the atomic release rate, and is conducive to integrated design; it does not crush the atomic cell, does not generate glass fragments, and there is no risk of damaging the internal devices of the device. In addition, in the present invention, a collection of elemental atoms is used. Compared with common chromate release sources of atoms, it has the advantages of a large atomic mass, a long service life, and a small release magnetic field.

[0054] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. An atomic release source, characterized in that, It includes a housing, an atomic cell, a heater, and an atomic block; The housing has opposite proximal and distal ends, and the distal end of the housing has an atomic release hole; The atomic cell includes a cell housing and a cell cover. The cell housing is installed inside the housing. The cell housing has an opening, and the cell cover is detachably sealed on the opening and is pressed by external air pressure. When the external air pressure of the cell housing drops to a certain level, the cell cover falls off; The atomic block is arranged inside the cell housing; The heater is installed inside the housing and is located outside the cell housing for heating the atomic block inside the cell housing.

2. The atomic release source according to claim 1, characterized in that, It further includes a connector, a vacuum flange, and a support column. The support column is installed between the housing and the vacuum flange, and the connector passes through the vacuum flange and is electrically connected to the heater.

3. The atomic release source according to claim 2, characterized in that, The housing includes a first housing and a second housing. The second housing is installed on one side of the first housing close to the distal end. One end of the support column is connected to the first housing, and the atomic release hole is formed on the outer wall of the second housing close to the distal end.

4. The atomic release source according to claim 2, characterized in that, The connector is a Feedthrough connector, and the vacuum flange is a CF vacuum flange.

5. The atomic release source according to claim 2, characterized in that, The cell housing is made of a hollow glass tube. The proximal end of the hollow glass tube is melted and sealed, and its distal end is polished smoothly. The cell cover is a glass sheet structure, and the side of the cell cover close to the cell housing is polished smoothly.

6. The atomic release source according to claim 5, characterized in that, The surface flatness of the distal end of the hollow glass tube and the side of the cell cover close to the cell housing is not greater than 10 μm.

7. The atomic release source according to claim 3, characterized in that, The heater includes an electric heating wire wound around the outside of the cell housing. The two electrically connected ends of the electric heating wire extend out from the proximal end of the first housing and are electrically connected to the connector.

8. The atomic release source according to claim 7, characterized in that, The electric heating wire is wound in a twisted pair manner.

9. The atomic release source according to claim 2, characterized in that, It further includes a sealing ring. The sealing ring is installed on the side of the vacuum flange close to the housing, and the edge of the vacuum flange is pressed into the sealing ring.

10. The atomic release source according to claim 2, characterized in that, The atomic block is a single isotope atom, a natural abundance atom, or a combination of multiple atoms.

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