Multi-reflection enhanced Rydberg atom microwave measuring device

Abstract

The invention discloses a multi-reflection enhanced Rydberg atom microwave measurement device, which relates to the technical field of microwave receiving and detection, and comprises a non-metal shell, a base, a detection light optical fiber input interface, a coupling light optical fiber input interface, a detection light module, a coupling light module, an interaction module and a third photoelectric detector, the nonmetal shell and the base are used for installing and fixing all elements; the detection light optical fiber input interface and the coupling light optical fiber input interface emit detection light and coupling light; the detection light module and the coupling light module are respectively arranged on a detection light path and a coupling light path, and the detection light and the coupling light are modulated and then enter the interaction module; the detection light and the coupling light are reflected for multiple times in the interaction module, and the third photoelectric detector receives the detection light leaving the interaction module; according to the invention, the interaction between light path multi-reflection enhanced light and atoms is utilized to effectively enhance the electromagnetic induction transparency effect, so that the sensitivity of the atomic microwave detection device for measuring the electric field is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of microwave receiving and detecting, and in particular to a multi-reflection enhanced Rydberg atom microwave measuring device. Background Art

[0002] Microwave communication is the most widely used radio communication method in modern times. Microwave reception and detection is an important part of microwave communication. Accurate, fast and sensitive reception and detection of microwave electric fields is the prerequisite for high-speed and low-error-rate microwave communication. At present, microwaves are usually received by dipole antennas. Dipole antennas have many disadvantages, such as: it is difficult to achieve absolute measurement of microwave electric fields, and calibration is required before use; detection sensitivity is limited by antenna size; and the operating frequency band is narrow. In recent years, microwave electric field sensing receiving devices based on Rydberg atoms have attracted widespread attention as a quantum radio response receiving device. It uses the Autler-Townes splitting (EIT-AT) effect of electromagnetic induced transparency (EIT) to achieve high sensitivity and high accuracy measurement of microwave electric field signals. Compared with traditional dipole antennas, it has the following main advantages: measurement sensitivity and spatial resolution far exceed traditional thermoelectric / thermosensitive microwave probes; it can trace back to the atomic transition frequency and measure the absolute value of the electric field strength; the size of the microwave electric field sensor is independent of the microwave wavelength, and has ultra-wide spectrum measurement capabilities from DC to terahertz; the sensitive probe has no metal parts, hardly absorbs and reflects electromagnetic waves, is highly concealed and resistant to electromagnetic damage.

[0003] At present, most microwave sensing receiving devices based on Rydberg atoms adopt a dual-light single-pass detection scheme. The spectral signal is obtained from the interaction between the probe light and the coupling light that passes through the atomic gas chamber once and the atoms. The signal strength depends on the strength of the interaction, which is affected by the strength of the probe light and the coupling light and the number of atoms. In specific experiments, since the intensity of the probe light and the coupling light affects the EIT signal intensity as well as the EIT spectral width, the intensity of the probe light and the coupling light is generally set within a certain range. Increasing the number of atoms participating in the interaction can effectively enhance the signal strength without introducing other effects. However, for the dual-light single-pass detection scheme, the number of atoms participating in the interaction cannot be further increased due to the limitation of the size of the atomic gas chamber, which therefore also limits the further improvement of the performance of microwave sensing measurement devices based on Rydberg atoms. Summary of the invention

[0004] The purpose of the present invention is to provide a multi-reflection enhanced dual-light atomic microwave measurement device to enhance the sensitivity of measuring microwave electric field intensity through a dual-light detection scheme.

[0005] The technical solution of the present invention is: to provide a multi-reflection enhanced Rydberg atomic microwave measurement device, the device comprising: a non-metallic housing and a base, a detection light fiber input interface, a coupling light fiber input interface, a detection light module, a coupling light module, an interaction module and a third photoelectric detector;

[0006] The non-metallic housing and base are used to install and fix all components. The non-metallic housing and base are transparent boxes with a removable cover on the top. The base is provided with a card slot processed according to the shape of the optical element, and each optical element is fixed with ultraviolet glue;

[0007] The detection light fiber input interface and the coupling light fiber input interface are installed on the side walls of the non-metallic housing and the base, and emit the detection light and the coupling light into the non-metallic housing and the base along the vertical direction of the side walls respectively;

[0008] The detection light module and the coupling light module are respectively arranged on the optical paths of the detection light and the coupling light, and respectively modulate the detection light and the coupling light and then inject them into the interaction module;

[0009] The interaction module comprises: an atomic gas chamber, a microwave source, a first plane reflector, and a second plane reflector; the first plane reflector and the second plane reflector are arranged in parallel, and their reflection surfaces are both facing inwards; an atomic gas chamber is arranged between the first plane reflector and the second plane reflector, and the interior of the atomic gas chamber is filled with Rydberg atoms; and the microwave source is arranged next to the atomic gas chamber;

[0010] The detection light is reflected onto either the first plane reflector or the second plane reflector, and the coupling light is also reflected onto either the first plane reflector or the second plane reflector. The detection light and the coupling light have the same incident angle, and multiple reflections occur between the first plane reflector and the second plane reflector. The optical paths of the detection light and the coupling light between the first plane reflector and the second plane reflector overlap, and the detection light and the coupling light are inverse optical paths to each other.

[0011] After the detection light and the coupled light enter the atomic gas chamber, they excite the rubidium atoms in a step-by-step manner, causing them to reach high-valence Rydberg states, realizing the EIT effect and making the intensity change of the detection light present a peak structure. The third photodetector receives the detection light leaving the interaction module. The third photodetector obtains the width of the microwave-induced EIT-AT splitting based on the intensity change of the detection light, thereby measuring the microwave electric field strength of the microwave source.

[0012] In any of the above technical solutions, further, the detection light module includes: a first half wave plate, a third half wave plate, a first polarization beam splitter prism, a first photodetector, a first acousto-optic modulator, a first quarter wave plate, a first lens, a first zero-degree reflector, and a first dichroic mirror;

[0013] The first half wave plate is arranged on the optical path of the detection light. The detection light enters the first half wave plate. The first half wave plate adjusts the polarization of the detection light. After the detection light is emitted, it is vertically incident on the first polarization beam splitter prism for splitting. One path is incident on the first photodetector to monitor the stability of the optical power, and the other path enters the first double-pass combination composed of the first acousto-optic modulator, the first quarter wave plate, the first lens, and the first zero-degree reflector to change the detection light frequency. This path of detection light is incident on the first acousto-optic modulator, the first quarter wave plate, and the first lens in sequence, and then is incident on the first zero-degree reflector along the normal direction of the first zero-degree reflector. After reflection, it is incident on the first lens, the first quarter wave plate, and the first acousto-optic modulator in sequence, and then is incident on the first polarization beam splitter prism along the original optical path. The first polarization beam splitter prism reflects the frequency-shifted detection light into the third half wave plate. The detection light is polarized by the third half wave plate and emitted, and then enters the first dichroic mirror. The first dichroic mirror reflects the detection light into the interaction module.

[0014] In any of the above technical solutions, further, the first acousto-optic modulator is placed at the focus of the first lens, the detection light is emitted in parallel from the first lens, and the first lens eliminates the influence of the diffraction angle change of the first acousto-optic modulator on the optical path.

[0015] In any of the above technical solutions, further, the coupling optical module includes: a second half wave plate, a fourth half wave plate, a second polarization beam splitter prism, a second photodetector, a second acousto-optic modulator, a second quarter wave plate, a second lens, a second zero-degree reflector, and a second dichroic mirror;

[0016] The coupling light module has a similar structure to the detection light module. The second dichroic mirror and the first dichroic mirror have different coatings. The first dichroic mirror can reflect the detection light, and the second dichroic mirror can reflect the coupling light. The detection light is not reflected by the second dichroic mirror and can directly pass through the second dichroic mirror.

[0017] In any of the above technical solutions, further, the first half wave plate and the second half wave plate are rotatable.

[0018] In any of the above technical solutions, further, the first plane reflector and the second plane reflector are both coated with a reflection enhancement film for the wavelength of the detection light and the coupling light.

[0019] In any of the above technical solutions, further, the detection light advances along the coupled light path in the interaction module, and after leaving the interaction module, the detection light is incident on and directly passes through the second dichroic mirror, and is incident on a third photodetector arranged on the non-metallic shell and the side wall of the base.

[0020] The beneficial effects of the present invention are:

[0021] The technical solution of the present invention improves the optical path form and sets two reflectors on both sides of the atomic gas chamber, so that the detection light and the coupling light can go back and forth in the atomic gas chamber for multiple times to increase the working distance, break through the limitation of the atomic gas chamber size, and effectively increase the number of interacting atoms, thereby achieving the purpose of improving the electric field measurement sensitivity index of the atomic microwave detection device. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The advantages of the above and additional aspects of the present invention will become apparent and easily understood in the description of the embodiments in conjunction with the following drawings, in which:

[0023] Figure 1 It is a schematic structural diagram of a multi-reflection enhanced Rydberg atom microwave measurement device according to an embodiment of the present invention.

[0024] Wherein: 1- non-metallic shell and base, 2- atomic gas chamber, 3- microwave source, 11- detection light fiber input interface, 12- coupling light fiber input interface, 21- first half wave plate, 22- second half wave plate, 23- third half wave plate, 24- fourth half wave plate, 31- first polarization beam splitter prism, 32- second polarization beam splitter prism, 41- first photodetector, 42- second photodetector, 43- third photodetector, 51- first acousto-optic modulator, 52- second acousto-optic modulator, 61- first quarter wave plate, 62- second quarter wave plate, 71- first lens, 72- second lens, 81- first zero degree reflector, 82- second zero degree reflector, 91- first dichroic mirror, 92- second dichroic mirror, A1- first plane reflector, A2- second plane reflector. DETAILED DESCRIPTION

[0025] In order to more clearly understand the above-mentioned purpose, features and advantages of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that the embodiments of the present invention and the features in the embodiments can be combined with each other without conflict.

[0026] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Therefore, the protection scope of the present invention is not limited to the specific embodiments disclosed below.

[0027] like Figure 1As shown, this embodiment provides a multi-reflection enhanced Rydberg atom microwave measurement device. This embodiment takes the currently widely used rubidium atom Rydberg state microwave receiving system as an example. The wavelengths of the detection light and the coupling light used in the system are 780nm and 480nm respectively. The device includes: a non-metallic shell and base 1, an atomic gas chamber 2, a microwave source 3, a detection light fiber input interface 11, a coupling light fiber input interface 12, a first half wave plate 21, a second half wave plate 22, a third half wave plate 23, a fourth half wave plate 24, and a second half wave plate 25. One-quarter wave plate 24, first polarization beam splitter prism 31, second polarization beam splitter prism 32, first photodetector 41, second photodetector 42, third photodetector 43, first acousto-optic modulator 51, second acousto-optic modulator 52, first quarter wave plate 61, second quarter wave plate 62, first lens 71, second lens 72, first zero-degree reflector 81, second zero-degree reflector 82, first dichroic mirror 91, second dichroic mirror 92, first plane reflector A1, second plane reflector A2.

[0028] The non-metallic shell and base 1 are a transparent box with an integrated structure. In this embodiment, the material thereof is G10 material synthesized from glass fiber and epoxy resin. A removable cover is provided on the top of the non-metallic shell and base 1 for easy maintenance. The non-metallic shell and base 1 have a number of corresponding card slots processed according to the shape of the optical elements installed therein, which facilitates the installation and fixation of the internal optical elements. The fixing method is UV glue fixing, which is not easily affected by ambient temperature and vibration.

[0029] The side walls of the non-metallic shell and the base 1 are installed with a detection light fiber input interface 11 and a coupling light fiber input interface 12; the detection light fiber input interface 11 emits detection light into the non-metallic shell and the base 1 along the vertical direction of the side wall where it is located, and in this embodiment, the detection light is 780nm light; the coupling light fiber input interface 12 emits coupling light into the non-metallic shell and the base 1 along the vertical direction of the side where it is located, and in this embodiment, the coupling light is 480nm light.

[0030] A detection light module is arranged on the optical path of the detection light, and the detection light module includes: a first half wave plate 21, a third half wave plate 23, a first polarization beam splitter prism 31, a first photodetector 41, a first acousto-optic modulator 51, a first quarter wave plate 61, a first lens 71, a first zero-degree reflector 81, and a first dichroic mirror 91; a coupling light module is arranged on the optical path of the coupling light, and the coupling light module has a similar structure to the detection light module, and the coupling light module includes: a second half wave plate 22, a fourth half wave plate 24, a second polarization beam splitter prism 32, a second photodetector 42, a second acousto-optic modulator 52, a second quarter wave plate 62, a second lens 72, a second zero-degree reflector 82, and a second dichroic mirror 92.

[0031] The structure of the detection optical module is introduced as an example. The coupling optical module is similar to it. The structure and optical path of the detection optical module are as follows:

[0032] The first half wave plate 21 is arranged on the optical path of the detection light. The detection light enters the first half wave plate 21. The first half wave plate 21 adjusts the polarization of the detection light. After the detection light is emitted, it is vertically incident on the first polarization splitting prism 31 for splitting. One path enters the first photodetector 41 to monitor the stability of the optical power, and the other path enters the first double-pass combination composed of the first acousto-optic modulator 51, the first quarter wave plate 61, the first lens 71, and the first zero-degree reflector 81 to change the detection light frequency. This path of detection light is incident on the first acousto-optic modulator 51, the first quarter wave plate 61, the first lens 71, and the first zero-degree reflector 81 in sequence. The frequency-shifted detection light is incident on the first polarization beam splitter prism 31, and then the detection light is incident on the first polarization beam splitter prism 31 along the normal direction of the first zero-degree reflector 81. After being reflected, the detection light is incident on the first lens 71, the first quarter-wave plate 61, and the first acousto-optic modulator 51 in sequence, and then incident on the first polarization beam splitter prism 31 along the original optical path. The first polarization beam splitter prism 31 reflects the frequency-shifted detection light into the third half-wave plate 23. The detection light is polarized by the third half-wave plate 23 and then emitted into the first dichroic mirror 91. The first dichroic mirror 91 reflects the detection light into the interaction module.

[0033] The first lens 71 is used to eliminate the influence of the diffraction angle change of the first acousto-optic modulator 51 on the optical path. The first acousto-optic modulator 51 is placed at the focus of the first lens 71 to ensure that the detection light will be emitted from the first lens 71 in parallel, so as to achieve the purpose that the optical path is not affected by the modulation frequency.

[0034] The first dichroic mirror 91 and the second dichroic mirror 92 have different coatings. The first dichroic mirror 91 can reflect the detection light, and the second dichroic mirror 92 can reflect the coupling light. The detection light is not reflected by the second dichroic mirror 92 and can directly pass through the second dichroic mirror 92 .

[0035] The intensity ratio between the detection light and the coupled light can be adjusted by rotating the first half wave plate 21 and the second half wave plate 22 .

[0036] In this embodiment, the center frequencies of the modulation signals of the first AOM 51 and the second AOM 52 are 110 MHz.

[0037] The interaction module includes: an atomic gas chamber 2, a microwave source 3, a first plane reflector A1, and a second plane reflector A2.

[0038] The first plane reflector A1 and the second plane reflector A2 are arranged in parallel, with their reflective surfaces facing inwards. The first plane reflector A1 and the second plane reflector A2 are both coated with a reflection enhancement film for the wavelength of the detection light and the coupling light.

[0039] An atomic gas chamber 2 is arranged between the first plane reflector A1 and the second plane reflector A2, and a microwave source 3 is arranged next to the atomic gas chamber 2; the interior of the atomic gas chamber 2 is filled with Rydberg atoms for interaction between light and microwave electric fields, and the spatial microwave electric field emitted by the microwave source 3 can be measured by further detecting the EIT-AT splitting produced by the coupled Rydberg state, and the interval of the spectrum splitting is proportional to the size of the microwave electric field. The signal-to-noise ratio of the EIT spectrum determines the sensitivity of the microwave electric field measurement.

[0040] After the detection light and the coupling light enter the atomic gas chamber 2, they excite the rubidium atoms in a step-by-step manner, causing the rubidium atoms to reach a high-valence Rydberg state, thereby realizing the EIT effect, that is, the detection light passing through the resonance point is almost not absorbed by the rubidium atoms. Specifically, when the optical frequency of the detection light or the coupling light is scanned, the intensity change of the detection light will present a peak structure.

[0041] The detection light is reflected from the first dichroic mirror 91 to either the first plane reflector A1 or the second plane reflector A2, and the coupling light is also reflected from the second dichroic mirror 92 to either the first plane reflector A1 or the second plane reflector A2 (in this embodiment, the detection light is incident on the first plane reflector A1, and the coupling light is incident on the second plane reflector A2). The incident angles of the detection light and the coupling light are the same, and multiple reflections occur between the first plane reflector A1 and the second plane reflector A2. The positions of the first dichroic mirror 91 and the second dichroic mirror 92 are adjusted (without adjusting the angle) so that the optical paths of the detection light and the coupling light between the first plane reflector A1 and the second plane reflector A2 coincide.

[0042] The detection light leaves the interaction module after multiple reflections along the same optical path as the coupling light and is incident on the second dichroic mirror 92. The detection light directly passes through the second dichroic mirror 92 and is incident on the third photodetector 43 arranged on the non-metallic housing and the base 1. The signal generated by the interaction can be reflected by the intensity change of the detection light finally hitting the third photodetector. The third photodetector 43 obtains the width of the microwave-induced EIT-AT splitting based on the intensity change of the detection light, thereby measuring the microwave electric field strength of the microwave source 3.

[0043] Adjusting the incident angle of the detection light and the coupling light on the first plane reflector A1 or the second plane reflector A2 can affect the number of round trips of the detection light and the coupling light in the atomic gas chamber 2 of the interaction module, increase the number of round trips of the detection light and the coupling light as much as possible, break through the limitation of the atomic gas chamber size, and effectively increase the action distance with the rubidium atoms, that is, increase the number of interacting rubidium atoms, thereby increasing the signal-to-noise ratio of the EIT spectrum and improving the sensitivity of microwave electric field measurement.

[0044] In summary, the present invention proposes a multi-reflection enhanced Rydberg atomic microwave measurement device, including: a non-metallic shell and base 1, a detection light fiber input interface 11, a coupling light fiber input interface 12, a detection light module, a coupling light module, an interaction module and a third photodetector 43.

[0045] The non-metallic shell and base 1 are used to install and fix all components. The non-metallic shell and base 1 are transparent boxes with a removable cover on the top. The base is provided with a card slot processed according to the shape of the optical element, and each optical element is fixed with ultraviolet glue.

[0046] The detection light fiber input interface 11 and the coupling light fiber input interface 12 are installed on the side walls of the non-metallic housing and the base 1, and emit detection light and coupling light into the non-metallic housing and the base 1 along the vertical direction of the side walls respectively.

[0047] The detection light module and the coupling light module are respectively arranged on the optical paths of the detection light and the coupling light, and respectively modulate the detection light and the coupling light and then inject them into the interaction module.

[0048] The interaction module includes: an atomic gas chamber 2, a microwave source 3, a first plane reflector A1, and a second plane reflector A2; the first plane reflector A1 and the second plane reflector A2 are arranged in parallel, and their reflection surfaces are both facing inward, the atomic gas chamber 2 is arranged between the first plane reflector A1 and the second plane reflector A2, the atomic gas chamber 2 is filled with Rydberg atoms, and the microwave source 3 is arranged next to the atomic gas chamber 2.

[0049] The detection light is reflected onto either the first plane reflector A1 or the second plane reflector A2, and the coupling light is also reflected onto either the first plane reflector A1 or the second plane reflector A2. The incident angles of the detection light and the coupling light are the same, and multiple reflections occur between the first plane reflector A1 and the second plane reflector A2, and the optical paths of the detection light and the coupling light overlap between the first plane reflector A1 and the second plane reflector A2.

[0050] After the detection light and the coupled light enter the atomic gas chamber 2, they excite the rubidium atoms in a step-by-step manner, causing the rubidium atoms to reach a high-valence Rydberg state, realizing the EIT effect, so that the intensity change of the detection light will present a peak structure. The third photodetector 43 receives the detection light leaving the interaction module.

[0051] The steps in the present invention can be adjusted in order, combined or deleted according to actual needs.

[0052] The units in the device of the present invention can be combined, divided and deleted according to actual needs.

[0053] Although the present invention is disclosed in detail with reference to the accompanying drawings, it should be understood that these descriptions are merely exemplary and are not intended to limit the application of the present invention. The scope of protection of the present invention is defined by the appended claims and may include various modifications, alterations and equivalents made to the invention without departing from the scope and spirit of the present invention.

Claims

1. A multi-reflection enhanced Rydberg atomic microwave measurement device, characterized in that: The device comprises: a non-metallic housing and a base (1), a detection light fiber input interface (11), a coupling light fiber input interface (12), a detection light module, a coupling light module, an interaction module and a third photoelectric detector (43); The non-metallic housing and base (1) are used to install and fix all components. The non-metallic housing and base (1) are transparent boxes with a removable cover on the top. The base is provided with a slot processed according to the shape of the optical element, and each optical element is fixed with ultraviolet glue. The detection light fiber input interface (11) and the coupling light fiber input interface (12) are installed on the side walls of the non-metallic housing and the base (1), and emit detection light and coupling light into the non-metallic housing and the base (1) along the vertical direction of the side walls respectively; The detection light module and the coupling light module are respectively arranged on the optical paths of the detection light and the coupling light, and respectively modulate the detection light and the coupling light and then inject them into the interaction module; The interaction module comprises: an atomic gas chamber (2), a microwave source (3), a first plane reflector A1, and a second plane reflector A2; the first plane reflector A1 and the second plane reflector A2 are arranged in parallel, with their reflection surfaces facing inwards; the atomic gas chamber (2) is arranged between the first plane reflector A1 and the second plane reflector A2; the atomic gas chamber (2) is filled with Rydberg atoms; and the microwave source (3) is arranged next to the atomic gas chamber (2); The detection light is reflected onto either the first plane reflector A1 or the second plane reflector A2, and the coupling light is also reflected onto either the first plane reflector A1 or the second plane reflector A2. The detection light and the coupling light have the same incident angle, and multiple reflections occur between the first plane reflector A1 and the second plane reflector A2. The optical paths of the detection light and the coupling light between the first plane reflector A1 and the second plane reflector A2 overlap, and the detection light and the coupling light are inverse optical paths to each other. After the detection light and the coupled light enter the atomic gas chamber (2), the rubidium atoms are excited in a step-by-step manner, so that the rubidium atoms reach a high-valence Rydberg state, realizing the EIT effect, so that the intensity change of the detection light will present a peak structure. The third photodetector (43) receives the detection light leaving the interaction module. The third photodetector (43) obtains the width of the microwave-induced EIT spectrum splitting based on the intensity change of the detection light, thereby measuring the microwave electric field intensity of the microwave source (3).

2. The multi-reflection enhanced Rydberg atomic microwave measurement device according to claim 1, characterized in that: The detection light module comprises: a first half wave plate (21), a third half wave plate (23), a first polarization beam splitter prism (31), a first photodetector (41), a first acousto-optic modulator (51), a first quarter wave plate (61), a first lens (71), a first zero-degree reflector (81), and a first dichroic mirror (91); The first half-wave plate (21) is arranged on the optical path of the detection light. The detection light enters the first half-wave plate (21). The first half-wave plate (21) adjusts the polarization of the detection light. After the detection light is emitted, it is vertically incident on the first polarization splitting prism (31) for splitting. One path enters the first photodetector (41) to monitor the stability of the optical power, and the other path enters the first double-pass combination composed of the first acousto-optic modulator (51), the first quarter-wave plate (61), the first lens (71), and the first zero-degree reflector (81) to change the detection light frequency. This path of detection light is incident on the first acousto-optic modulator (51), the first quarter-wave plate (61), the first lens (71), and the first zero-degree reflector (81) in sequence. The detection light is incident on a first wave plate (61) and a first lens (71), and then enters the first zero-degree reflection mirror (81) along the normal direction of the first zero-degree reflection mirror (81). After being reflected, the detection light is incident on the first lens (71), the first quarter-wave plate (61), and the first acousto-optic modulator (51) in sequence, and then enters the first polarization beam splitter prism (31) along the original optical path. The first polarization beam splitter prism (31) reflects the frequency-shifted detection light into a third half-wave plate (23). The detection light is polarized by the third half-wave plate (23) and then emitted into a first dichroic mirror (91). The first dichroic mirror (91) reflects the detection light into an interaction module.

3. The multi-reflection enhanced Rydberg atomic microwave measurement device according to claim 2, characterized in that: The first acousto-optic modulator (51) is placed at the focus of the first lens (71), the detection light is emitted in parallel from the first lens (71), and the first lens (71) eliminates the influence of the diffraction angle change of the first acousto-optic modulator (51) on the optical path.

4. The multi-reflection enhanced Rydberg atomic microwave measurement device according to any one of claims 2 and 3, characterized in that: The coupling optical module comprises: a second half wave plate (22), a fourth half wave plate (24), a second polarization beam splitter prism (32), a second photodetector (42), a second acousto-optic modulator (52), a second quarter wave plate (62), a second lens (72), a second zero-degree reflector (82), and a second dichroic mirror (92); The coupling light module has a similar structure to the detection light module. The second dichroic mirror (92) and the first dichroic mirror (91) have different coatings. The first dichroic mirror (91) can reflect the detection light, and the second dichroic mirror (92) can reflect the coupling light. The detection light is not reflected by the second dichroic mirror (92) and can directly pass through the second dichroic mirror (92).

5. The multi-reflection enhanced Rydberg atomic microwave measurement device according to any one of claims 2 and 4, characterized in that: The first half wave plate (21) and the second half wave plate (22) are rotatable.

6. The multi-reflection enhanced Rydberg atomic microwave measurement device according to claim 1, characterized in that: The first plane reflector A1 and the second plane reflector A2 are both coated with a reflection enhancement film for the wavelength of the detection light and the coupling light.

7. The multi-reflection enhanced Rydberg atomic microwave measurement device according to claim 4, characterized in that: The detection light advances along the coupled light path in the interaction module, and after leaving the interaction module, it enters and directly passes through the second dichroic mirror (92), and enters the third photodetector (43) arranged on the side wall of the non-metallic housing and the base (1).

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