Probe structure for disturbance suppression of Rydberg atomic electric field based on multilayer dielectric method

Abstract

The invention discloses a probe structure for disturbance suppression of a Rydberg atomic electric field based on a multilayer dielectric method. The probe structure comprises an atomic gas chamber, a dielectric base and a dielectric insert, the medium base and the medium insertion sheet are made of a non-conductive medium material; the atomic gas chamber is arranged on the medium base, and at least two medium insertion pieces are separately arranged on the two sides of the medium base and are attached to the two opposite sides of the atomic gas chamber respectively. A complex micromachining technology is not needed, dependence on the electromagnetic regulation and control capacity of the metamaterial is avoided, disturbance of the atomic gas chamber to an electric field is compensated through the thickness of the medium insertion piece, the atomic detection sensitivity of the large-size atomic gas chamber is allowed to be improved, and the method is suitable for atomic gas chambers of various frequencies and sizes; according to the invention, Rydberg atomic electric field disturbance suppression is realized based on a multilayer dielectric method, and more accurate and reliable signal measurement and reduction can be realized.

Description

Technical Field

[0001] The present invention relates to the technical field of microwave electric field measurement, and particularly to a probe structure for suppressing the electric field perturbation of Rydberg atoms based on the multi-layer dielectric method. Background Art

[0002] The electric field strength is one of the seven key quantities of radio metrology defined by the International Committee for Weights and Measures. Currently, a dipole antenna is generally used as an electric field probe to measure the field to be measured. This method requires known electric field calibration (the traceability chain is complex), and there are problems such as the perturbation of the measured field by metal components, the resolution being limited by the antenna size (the sensitivity of electrically small antennas is low), and the high uncertainty.

[0003] The Rydberg atom antenna converts the electric field measurement into an accurate frequency measurement, and finally realizes the measurement of the electric field strength by optically detecting the splitting width. This measurement method has the advantages of self-calibration and directly tracing the electric field amplitude to the International System of Units (SI). However, although Rydberg atoms can be used for precise measurement of microwave electric fields, there are still many problems in establishing a quantum metrology benchmark based on this method. Among them, the standing wave effect, electromagnetic scattering, and polarization mismatch perturbation effects of the atomic cell are the largest error terms in microwave electric field measurement. This is particularly obvious at high frequencies or with larger cell sizes.

[0004] The current schemes for suppressing the electromagnetic perturbation of the atomic cell mainly include reducing the cell size, thinning the atomic cell wall, and regulating the electromagnetic metasurface structure. The smaller the ratio of the atomic cell size to the microwave wavelength, the weaker the scattering and standing wave effects of the cell on the electric field. However, after reducing the atomic cell size, the effective interaction length between light and atoms decreases, restricting the signal detection efficiency. The thin-wall design of the atomic cell (such as the wall thickness ≤ 1 mm) makes the cell vulnerable to physical impact damage. The electromagnetic metasurface structure processes the metasurface on the surface of a borosilicate glass or quartz atomic cell through processes such as photolithography, metal deposition, and bonding. This method has high requirements for the accuracy of the periodic array structure, increasing the manufacturing difficulty and cost. Summary of the Invention

[0005] Aiming at the deficiencies of the prior art, the present invention aims to provide a probe structure for suppressing the electric field perturbation of Rydberg atoms based on the multi-layer dielectric method. By adding a non-conductive dielectric material outside the atomic cell, the perturbation of the atomic cell on the electric field can be suppressed, and it can be applied to atomic cells of various sizes within a wide frequency band range.

[0006] To achieve the above object, the present invention adopts the following technical solutions: A probe structure for suppressing the electric field perturbation of Rydberg atoms based on the multi-layer dielectric method, comprising an atomic gas cell, a dielectric base, and dielectric inserts; the dielectric base and the dielectric inserts are made of non-conductive dielectric materials; the atomic gas cell is disposed on the dielectric base, and at least two dielectric inserts are separably disposed on both sides of the dielectric base and are respectively attached to the opposite sides of the atomic gas cell.

[0007] Further, an air cell groove is provided on the dielectric base, and the bottom of the atomic gas cell is embedded in the air cell groove.

[0008] Further, two insertion posts are provided on both sides of the dielectric base, and slots are provided on the opposite sides of the two insertion posts on the same side, and the upper ends of the slots are of an open structure; the two sides of the dielectric insert are respectively inserted into the slots of the two insertion posts on the corresponding side.

[0009] Further, the atomic gas cell is cylindrical, cube-shaped or cuboid-shaped.

[0010] As a more preferred solution, the atomic gas cell is cube-shaped.

[0011] Further, the glass shell of the atomic gas cell is made of high borosilicate glass, quartz glass or sapphire.

[0012] As a more preferred solution, the glass shell of the atomic gas cell is made of high borosilicate glass with a dielectric constant of 4.4 and a dielectric loss of 0.00037.

[0013] Further, the dielectric base and the dielectric inserts are made of the same non-conductive dielectric material, and the non-conductive dielectric material is alumina ceramic, polyether ether ketone, acrylonitrile / butadiene / styrene copolymer plate or polytetrafluoroethylene.

[0014] Further, the dielectric base, the dielectric inserts and the glass shell of the atomic gas cell are polished precisely to a surface roughness of <10 nm.

[0015] The beneficial effects of the present invention are as follows: 1. The present invention compensates for the electric field perturbation of the atomic gas cell through the thickness of the dielectric inserts made of non-conductive dielectric materials, allows large-sized atomic gas cells to improve atomic detection sensitivity, is applicable to atomic gas cells of various frequencies and sizes, does not require complex microfabrication processes, and does not rely on the electromagnetic regulation ability of metamaterials; 2. The present invention realizes the suppression of the electric field perturbation of Rydberg atoms based on the multi-layer dielectric method, and can achieve more accurate and reliable signal measurement and restoration. Description of the Drawings

[0016] Figure 1 It is a schematic diagram of the probe structure in the embodiment of the present invention (the thickness of the dielectric insert is 1 mm); Figure 2Schematic diagram of the probe structure in the embodiment of the present invention (the thickness of the dielectric insert is 5 mm); Figure 3 Schematic diagram of the dielectric base in the probe structure in the embodiment of the present invention; Figure 4 Electric field distribution diagram at different positions of the atomic gas cell at 17.04 GHz obtained from the experiment in the embodiment of the present invention; Figure 5 Relationship between microwave frequency and coefficient of variation under different combinations of dielectric insert thicknesses obtained from the experiment in the embodiment of the present invention. Detailed implementation manners

[0017] The present invention will be further described below in conjunction with the drawings. It should be noted that this embodiment is based on the technical solution of the present application, and detailed implementation manners and specific operation procedures are given, but the protection scope of the present invention is not limited to this embodiment. Embodiment 1

[0018] This embodiment provides a probe structure for suppressing the electric field perturbation of Rydberg atoms based on the multi-layer dielectric method. As Figures 1-3 shown, it includes an atomic gas cell 1, a dielectric base 2, and dielectric inserts 3; the dielectric base 2 and the dielectric inserts 3 are made of non-conductive dielectric materials; the atomic gas cell 1 is arranged on the dielectric base 2, and at least two dielectric inserts 3 are detachably arranged on both sides of the dielectric base and are respectively attached to the opposite sides of the atomic gas cell.

[0019] In this embodiment, an air cell groove 21 is provided on the dielectric base 2, and the bottom of the atomic gas cell 1 is embedded in the air cell groove 21.

[0020] In this embodiment, two insertion posts 22 are provided on both sides of the dielectric base 2, and slots 23 are provided on the opposite sides of the two insertion posts 22 on the same side. The upper end of the slot 23 is of an open structure; both sides of the dielectric insert 3 are respectively inserted into the slots 23 of the two insertion posts 22 on the corresponding side. When installing the dielectric insert, both sides of the dielectric insert 3 are respectively inserted from the upper ends of the slots 23 of the two insertion posts 22. When the dielectric insert needs to be replaced, the dielectric insert 3 can be pulled out upward to complete the separation from the dielectric base 2. Thus, the reflection coefficient can be reduced by replacing dielectric inserts with different thicknesses. As Figure 1 and Figure 2 , Figure 1 the thickness of the dielectric insert in Figure 2 is 1 mm, and the thickness of the dielectric insert in

[0021] Further, the atomic gas cell 1 can be cylindrical, cube-shaped, or cuboid-shaped. In this embodiment, a cube shape is adopted, which is more conducive to adapting to the design and processing of the dielectric base and the dielectric insert. When a cylindrical atomic gas cell is used, the dielectric insert can adopt an annular structure, and a similar perturbation suppression effect can be achieved by adjusting the thickness of the ring.

[0022] Further, the glass shell of the atomic gas cell 1 can be made of borosilicate glass, quartz glass, or sapphire. In this embodiment, borosilicate glass with a dielectric constant of 4.4 and a dielectric loss of 0.00037 is adopted, which has excellent heat resistance and can be used for gas cells with complex structures.

[0023] Further, the dielectric base 2 can be made of non-conductive dielectric materials such as alumina ceramic (ε = 9.8), polyether ether ketone (PEEK) (ε = 3.2), acrylonitrile / butadiene / styrene copolymer board (ABS) (ε = 2.8), polytetrafluoroethylene (ε = 2.1), etc. Specifically, materials with a dielectric constant matching the target frequency band can be selected according to the target frequency band.

[0024] Further, the dielectric insert 3 is made of the same material as the dielectric base 2.

[0025] In this embodiment, the dielectric base 2, the dielectric insert 3, and the glass shell of the atomic gas cell 1 are precision polished to a surface roughness of <10 nm, so as to ensure the gapless fit between the dielectric insert and the atomic gas cell. Embodiment 2

[0026] This embodiment further illustrates the performance of the probe structure described in Embodiment 1 through experiments.

[0027] Using the two-photon excitation scheme, the ground-state atoms are excited to the Rydberg state, where the probe light is 780 nm and the coupling light is 480 nm. After the probe light and the coupling light are collimated, they are transmitted in opposite directions in a collinear manner through the atomic gas cell filled with rubidium vapor. After the laser enters the atomic gas cell, the rubidium atoms are excited to the Rydberg state, forming an electromagnetically induced transparency (EIT) window. Further, a microwave electric field is added to couple the Rydberg transition, forming an EIT-AT splitting. The photodetector is used for signal acquisition, and after data processing and calculation, the electric field strength value is finally output.

[0028] By moving the position of the atomic gas cell in the microwave propagation direction, the change in the electric field strength on the laser path is measured, and the perturbation of the atomic gas cell is characterized by the coefficient of variation of the microwave electric field distribution at different positions. The coefficient of variation is the ratio of the standard deviation to the mean value, that is:

[0029] Among them, it represents the standard deviation of the electric field strength at different positions in the atomic gas chamber, and is the average value. The larger the coefficient of variation indicates that the greater the degree of dispersion of the electric field strength at different positions in the atomic gas chamber, that is, the greater the disturbance of the atomic gas chamber is characterized.

[0030] This embodiment takes the low-disturbance test with a microwave frequency of 17.04 GHz as an example. An atomic gas chamber with a cubic structure is used, with a side length of 30 mm and a wall thickness of 1 mm, made of high borosilicate glass. By using electromagnetic simulation software to simulate the plane wave incident on the atomic gas chamber, the electric field strength distributions at different positions inside the atomic gas chamber with the medium inserts attached to both sides (i.e., there are multiple layers of media with a thickness of 2 mm) and without the medium inserts attached to both sides (i.e., without multiple layers of media) at 17.04 GHz are obtained, as Figure 4 shown. It can be seen that when there are multiple layers of media, the fluctuation of the electric field strength received by the atomic gas chamber at different positions is smaller, and the coefficient of variation is 7%. When there are no multiple layers of media, the fluctuation of the electric field strength received by the atomic gas chamber at different positions is larger, and the coefficient of variation is 13%. Therefore, the probe structure described in this embodiment can effectively reduce the interference of the atomic gas chamber itself on the electromagnetic signal and achieve accurate measurement.

[0031] Figure 5 The relationship between the microwave frequency and the coefficient of variation under different medium insert thicknesses is shown. The smaller the coefficient of variation indicates that the lower the disturbance of the probe to the electric field. Taking the coefficient of variation of 10% as the cut-off line, by using different thicknesses of medium inserts, the low-disturbance characteristic design of the Rydberg atom electric field probe in a wide frequency band range can be achieved.

[0032] It can be seen that the probe structure of Embodiment 1 can reduce the coefficient of variation of the electric field disturbance by 46% (the coefficient of variation drops from 13% to 7%) through the setting of the medium inserts, and at the same time, multiple reflections caused by the interlayer air gap can be avoided through precision machining. The probe structure of this embodiment can be combined with high-precision optical detection and signal processing and is applicable to fields such as quantum sensing and non-destructive testing.

[0033] For those skilled in the art, various corresponding changes and deformations can be given according to the above technical solutions and concepts, and all these changes and deformations should be included in the protection scope of the claims of the present invention.

Claims

1. A probe structure for suppressing the electric field perturbation of Rydberg atoms based on the multi-layer dielectric method, characterized in that, It includes an atomic gas chamber, a dielectric base, and dielectric inserts; the dielectric base and the dielectric inserts are made of non-conductive dielectric materials; the atomic gas chamber is disposed on the dielectric base, and at least two dielectric inserts are detachably disposed on both sides of the dielectric base and are respectively attached to the opposite sides of the atomic gas chamber.

2. The probe structure according to claim 1, wherein, An air chamber groove is provided on the dielectric base, and the bottom of the atomic gas chamber is embedded in the air chamber groove.

3. The probe structure according to claim 1, characterized in that, Two insertion posts are provided on both sides of the dielectric base, and slots are provided on the opposite sides of the two insertion posts on the same side, and the upper ends of the slots are of an open structure; the two sides of the dielectric insert are respectively inserted into the slots of the two insertion posts on the corresponding side.

4. The probe structure according to claim 1, wherein The atomic gas chamber is cylindrical, cube-shaped or cuboid.

5. The probe structure according to claim 4, wherein, The atomic gas chamber is cube-shaped.

6. The probe structure according to claim 1, characterized in that, The glass shell of the atomic gas chamber is made of high borosilicate glass, quartz glass or sapphire.

7. The probe structure according to claim 6, wherein, The glass shell of the atomic gas chamber is made of high borosilicate glass with a dielectric constant of 4.4 and a dielectric loss of 0.00037.

8. The probe structure according to claim 1, characterized in that, The dielectric base and the dielectric inserts are made of the same non-conductive dielectric material, and the non-conductive dielectric material is alumina ceramic, polyether ether ketone, acrylonitrile / butadiene / styrene copolymer plate or polytetrafluoroethylene.

9. The probe structure according to claim 1, characterized in that, The dielectric base, the dielectric inserts and the glass shell of the atomic gas chamber are precision polished to a surface roughness of <10 nm.

Images