Superheterodyne detection apparatus and method for optimizing response of Rydberg atom microwave pulse signals

Abstract

This invention relates to a superheterodyne detection device and method for optimizing the microwave pulse signal response of Rydberg atoms. The device includes an atomic gas cell, a probe laser source, a coupling laser source, a beam splitter module, a local oscillator microwave source, a signal microwave source, a horn antenna, a photodetector, and a signal processing unit. The beam splitter module divides the probe light and coupling light into two paths each, forming a dual-path collinear through-beam detection structure within a single gas cell. The probe light and coupling light excite atoms to Rydberg states, while the local oscillator microwave field couples with adjacent Rydberg states of the frequency-sweeping test microwave field, achieving superheterodyne detection. The signal processing unit performs spectral analysis on the two signals separately, compares the amplitudes, and extracts the maximum value. This invention, through a single-cell dual-path collinear through-beam detection and dual-path amplitude comparison and extraction mechanism, simplifies the structure, reduces costs, effectively improves the signal-to-noise ratio and anti-interference capability of the signal response, and broadens the instantaneous bandwidth, achieving high-performance broadband microwave pulse signal detection.

Description

Technical Field

[0001] This invention relates to the field of microwave sensing technology, and in particular to a superheterodyne detection device and method for optimizing the microwave pulse signal response of Rydberg atoms. Background Technology

[0002] Due to their extremely high polarizability, large electric dipole moment, and high sensitivity to microwave electric fields, Rydberg atoms have shown important application value in microwave signal detection, communication, and radar. As a result, microwave pulse detection technology based on Rydberg atoms has attracted widespread attention.

[0003] Traditional microwave pulse signal detection devices based on Rydberg atoms typically employ a single-path detection structure, relying solely on a single optical path for atom excitation and signal acquisition. This single-path structure has significant limitations: firstly, single-path detection is susceptible to factors such as uneven atomic density distribution within the atomic chamber, fluctuations in the power of the probe and coupling beams, and environmental electromagnetic noise, leading to unstable signal response amplitude and low signal-to-noise ratio, making it difficult to achieve reliable detection with high sensitivity; secondly, the instantaneous bandwidth coverage of single-path detection is limited, with significantly weakened signal response in certain frequency bands, resulting in detection blind zones and failing to meet the detection requirements of high-bandwidth, wide-frequency microwave pulse signals.

[0004] To overcome the shortcomings of single-channel detection, existing technologies have also developed schemes that employ multiple atomic chambers to achieve multi-channel detection. However, the multi-chamber structure not only significantly increases the size of the device, the number of optical elements, and the manufacturing cost, but also introduces channel differences due to inconsistencies in parameters such as temperature, atomic density, and optical path alignment between chambers. This leads to a significant increase in the complexity of system calibration and adjustment, which is not conducive to engineering applications.

[0005] Chinese patent application publication number CN121324757A discloses a Rydberg atom microwave receiver with arbitrary instantaneous bandwidth, including a probe laser generator, a probe beam splitter module, a coupling laser, a coupling beam splitter module, a Rydberg atom vapor cell array, a microwave frequency comb source, a gradient Stark field application module, a dichroic mirror, and a photodetector array. This scheme achieves linear superposition of multiple narrowband instantaneous bandwidths through the synergistic design of the gradient Stark field and the Rydberg atom vapor cell array, combined with the multi-tooth matching characteristics of the microwave frequency comb. However, the single-sided instantaneous bandwidth of a single atom cell in this scheme is typically only on the order of 10MHz. To achieve a practical instantaneous bandwidth such as 420MHz, an array of up to 21 Rydberg atom vapor cells is required, along with a complex gradient Stark field application module. Furthermore, extremely high laser power is needed to cover the excitation of multiple cells, resulting in an extremely complex system structure, large size, and significantly increased cost, limiting its application in scenarios requiring lightweight and low-cost solutions.

[0006] In summary, existing microwave pulse detection technologies based on Rydberg atoms suffer from unstable signal response, limited bandwidth, and weak anti-interference capabilities when using a single-channel structure, while multi-cell schemes face challenges such as complex system structure, high cost, and difficult calibration. Therefore, there is an urgent need for a high-performance microwave detection scheme that can simplify the device structure while effectively improving the microwave pulse signal response amplitude, broadening the detection bandwidth, and enhancing anti-interference capabilities. Summary of the Invention

[0007] The purpose of this invention is to overcome the defects of the prior art by providing a superheterodyne detection device and method for optimizing the Rydberg atom microwave pulse signal response. The aim is to simplify the device structure while widening the instantaneous bandwidth of the Rydberg atom microwave pulse detection and improving the signal-to-noise ratio of the signal response.

[0008] The objective of this invention can be achieved through the following technical solutions: One aspect of the present invention provides a superheterodyne detection device for optimizing the microwave pulse signal response of Rydberg atoms, comprising: Atomic gas chambers, filled with atomic vapor that can be excited to the Rydberg state (such as alkali metal cesium). 133 Cs, Rubidium 87 Rb); A probe laser source, used to generate a probe laser; A coupled laser source, used to generate coupled laser light; The first beam splitting module is used to split the detection laser into a first detection beam and a second detection beam; The second beam splitting module is used to split the coupled laser into a first coupled beam and a second coupled beam. Local oscillator microwave source, used to generate local oscillator microwave field; A signal microwave source, used to generate the microwave signal to be tested for frequency scanning; A horn antenna is used to radiate the local oscillator microwave field and the microwave signal to be measured to the atomic gas cell; A first photodetector is used to receive the first probe light passing through the atomic gas cell and convert it into a first electrical signal; The second photodetector is used to receive the second probe light passing through the atomic gas cell and convert it into a second electrical signal; The signal processing unit is connected to the first photodetector and the second photodetector respectively, and is used to perform spectrum analysis on the first electrical signal and the second electrical signal respectively to obtain the first response signal and the second response signal, and compare the amplitude of the first response signal and the second response signal to extract the response signal with the larger amplitude as the output. The optical path is configured such that the first probe light and the first coupling light enter the atomic gas cell in a collinear opposing manner, and that the second probe light and the second coupling light enter the atomic gas cell in a collinear opposing manner.

[0009] As a preferred technical solution, the frequencies of the probe laser and the coupling laser are configured to enable the atoms in the atomic chamber to form a four-level coherent system: the probe laser couples the ground state |1> to the intermediate state |2>, the coupling laser couples the intermediate state |2> to the Rydberg state |3>, and the local oscillator microwave field and the microwave signal to be measured are coupled together to the Rydberg state |3> to the adjacent Rydberg state |4>.

[0010] As a preferred technical solution, the first beam splitting module includes: An 852nm 45° semi-transparent and semi-reflective mirror is used to split the probe laser into a first path of reflected probe light and a second path of transmitted probe light; An 852nm 45° total reflection mirror is used to reflect the second probe light parallel to the first probe light; The second beam splitting module includes: A 509nm semi-transparent / semi-reflective / 852nm anti-reflective 45° dichroic mirror is used to split the coupled laser into a first path of reflected coupled light and a second path of transmitted coupled light. A 509nm semi-transparent and semi-reflective / 852nm anti-reflective 45° dichroic mirror is used to highly reflect the coupling laser wavelength and highly transmit the probe laser wavelength, and is used to split the coupling laser into a first path of reflected coupling light and a second path of transmitted coupling light. A 509nm total reflection / 852nm anti-reflection 45° dichroic mirror is used to reflect the second coupled light into parallel to the first coupled light. Specifically, the first probe light and the first coupling light are collinearly incident on the same straight line and enter the atomic gas chamber, while the second probe light and the second coupling light are collinearly incident on another straight line and enter the atomic gas chamber.

[0011] As a preferred technical solution, the 509nm semi-transparent / semi-reflective / 852nm anti-reflective 45° dichroic mirror is highly reflective of the coupled laser wavelength and highly transparent of the probe laser wavelength; the device also includes a light absorber for absorbing the coupled laser reflected by the dichroic mirror.

[0012] As a preferred technical solution, the atoms in the atomic vapor are cesium atoms or rubidium atoms.

[0013] As a preferred technical solution, the atoms in the atomic vapor are cesium atoms, the wavelength of the detection laser is 852 nm, the wavelength of the coupling laser is 509 nm, and the ground state |1> is 6S. 1 / 2 The intermediate state |2> is 6P 3 / 2.

[0014] As a preferred technical solution, the signal processing unit includes a spectrum analysis unit and a comparator, which are used to perform spectrum analysis on the first electrical signal and the second electrical signal respectively to obtain an intermediate frequency signal, and compare the amplitude of the intermediate frequency signal to extract the one with the larger amplitude as the response signal.

[0015] As a preferred technical solution, the frequency of the coupled laser source is tunable to optimize atomic coherence through detuning.

[0016] Another aspect of the present invention provides a superheterodyne detection method for optimizing the microwave pulse signal response of Rydberg atoms, implemented based on the aforementioned superheterodyne detection device, the method comprising the following steps: Construct an atomic gas chamber filled with alkali metal atomic vapor; The probe laser is divided into a first probe beam and a second probe beam, and the coupling laser is divided into a first coupling beam and a second coupling beam; The first probe light and the first coupling light are made to enter the atomic gas cell in a collinear opposing manner, and the second probe light and the second coupling light are made to enter the atomic gas cell in a collinear opposing manner. The local oscillator microwave field and the frequency-scanning microwave signal to be measured are radiated into the atomic gas cell; The frequencies of the probe laser and the coupling laser are configured to cause the atoms in the atomic chamber to form a four-level coherent system: the probe laser couples the ground state |1> to the intermediate state |2>, the coupling laser couples the intermediate state |2> to the Rydberg state |3>, and the local oscillator microwave field and the microwave signal to be measured are coupled together to the Rydberg state |3> to the adjacent Rydberg state |4>. The first and second probe beams passing through the atomic gas cell are received respectively and converted into a first electrical signal and a second electrical signal. Perform spectrum analysis on the first electrical signal and the second electrical signal respectively to obtain the first response signal and the second response signal; The amplitudes of the first response signal and the second response signal are compared, and the response signal with the larger amplitude is extracted as the detection result.

[0017] As a preferred technical solution, the spectrum analysis includes: performing frequency difference analysis between the first electrical signal and the second electrical signal and the local oscillator microwave frequency to obtain an intermediate frequency signal, wherein the response signal is the amplitude of the intermediate frequency signal.

[0018] Compared with the prior art, the present invention has at least one of the following beneficial effects: (1) The device structure is simplified: Traditional multi-chamber schemes introduce multiple atomic gas chambers and gradient field modules to broaden the bandwidth, resulting in complex system structure, large size, high cost and difficult calibration. In this regard, the present invention divides the detection laser and coupling laser into two paths by a beam splitting module, and constructs a dual-path collinear opposing optical architecture in a single atomic gas chamber. Dual-path synchronous detection can be achieved without adding additional atomic gas chambers and supporting complex electric field modules, which simplifies the device structure and reduces the size, manufacturing cost and system calibration difficulty.

[0019] (2) Optimize pulse signal response: Traditional single-path detection structures are easily affected by factors such as uneven atomic density distribution in the atomic gas chamber and laser power fluctuations, resulting in unstable signal response amplitude and low signal-to-noise ratio. In this regard, the present invention uses the first and second photodetectors to receive two detection optical signals respectively, and performs amplitude comparison and maximum value extraction on the dual signals through the signal processing unit. It can automatically avoid the detection optical path with weaker response and always retain the effective signal with the highest signal-to-noise ratio, thereby effectively improving the peak amplitude of the signal response and the anti-interference ability of the system in complex environments.

[0020] (3) Widening the bandwidth: The instantaneous bandwidth coverage of traditional single-channel detection is limited, which is difficult to meet the detection requirements of high-bandwidth microwave pulse signals. This invention combines superheterodyne detection technology to perform spectrum analysis on the frequency-sweeping microwave signal under test, and gives a general four-level coherent system. It also integrates a dual-channel peak extraction mechanism, breaking the limitation of narrow instantaneous bandwidth of single-channel detection. The actual measurement shows that the instantaneous bandwidth can be effectively extended from the maximum of about 26.7MHz in a single channel to more than 34.5MHz, realizing high-sensitivity detection of broadband microwave pulse signals. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the superheterodyne detection device for optimizing the microwave pulse signal response of the Rydberg atom in the embodiment; Figure 2 This is a schematic diagram of energy level transitions in a four-level coherently coupled system as shown in the example. Figure 3 The above is a spectral response curve of the first and second signals from the dual-path detection in the embodiment. Figure 4 This is a graph of the maximum response signal extracted after dual-channel amplitude comparison in the embodiment; Figure 5 This is a flowchart illustrating the superheterodyne detection method for optimizing the microwave pulse signal response of the Rydberg atom, as shown in the examples. Among them, 1. Atomic gas cell, 2. Horn antenna, 3. Local oscillator microwave source, 4. Microwave field of the signal to be measured, 5. 852nm 45° total reflection mirror, 6. 852nm 45° semi-transparent and semi-reflective mirror, 7. Light absorber, 8. 509nm total reflection / 852nm anti-reflection 45° dichroic mirror, 9. 509nm semi-transparent and semi-reflective / 852nm anti-reflection 45° dichroic mirror, 10. Photodetector. Detailed Implementation

[0022] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0023] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0024] Example 1 To address the problems existing in the prior art, this embodiment provides a superheterodyne detection device for optimizing the microwave pulse signal response of Rydberg atoms. The aim is to broaden the instantaneous bandwidth of Rydberg atom microwave pulse detection and improve the signal-to-noise ratio of the signal response by designing a dual-channel amplitude comparison and extraction mechanism, thereby simplifying the device structure.

[0025] The core of this embodiment is to utilize the synergistic effect of the electromagnetic induction transparency (EIT) of Rydberg atoms and superheterodyne detection technology to achieve a high-bandwidth response to microwave pulse signals. The principle of superheterodyne detection is to perform difference frequency processing on the microwave pulse signal to be measured and the local oscillator microwave field, converting the high-frequency microwave signal into a low-frequency intermediate-frequency signal, thereby reducing signal processing difficulty and increasing detection bandwidth. The core of this embodiment lies in solving the problems of narrow bandwidth and low signal-to-noise ratio in traditional single-channel detection through a single-cell dual-path collinear beam-through structure and a dual-path peak extraction mechanism.

[0026] Please see Figure 1 This is a schematic diagram of the experimental setup. This embodiment employs a single-chamber, dual-path collinear beam-beam structure, where two probe beams and a coupling beam act on different regions of the atomic gas chamber, effectively mitigating the influence of uneven atomic density within the chamber.

[0027] Taking cesium atoms as an example, the atomic gas chamber 1 is filled with cesium atom vapor, serving as the medium for interaction with the microwave field. The horn antenna 2 is used to radiate the local oscillator microwave field 3 and the signal microwave field 4 to be measured into the atomic gas chamber 1 in free space. The local oscillator microwave field 3 provides frequency-stable local oscillation microwaves, forming a difference frequency signal with the signal microwave field to be measured (i.e., the signal microwave source 4). The signal microwave field adopts a frequency-sweeping operating mode to realize the superheterodyne detection of broadband microwave signals. The detection laser passes through an 852nm 45° semi-transparent and semi-reflective mirror 6, splitting the 852nm detection laser power into two equal beams to detect the superheterodyne signal of the atoms.

[0028] The reflected light enters atomic gas cell 1 horizontally, while the transmitted light passes through an 852nm 45° total reflection mirror 5, whose optical path direction is vertically adjusted, and then enters atomic gas cell 1 horizontally, forming a single-cell dual-path detection structure. The coupled laser, collinear with the detection light, passes through a 509nm semi-transparent / semi-reflective / 852nm anti-reflection 45° dichroic mirror 9 from the other side of the gas cell, splitting the 509nm coupled laser power into two beams. The reflected light enters atomic gas cell 1 collinearly with the first detection laser, while the transmitted light passes through a 509nm total reflection / 852nm anti-reflection 45° dichroic mirror 8, whose optical path direction is vertically adjusted, and then enters atomic gas cell 1 collinearly with the second detection laser. After passing through the atomic gas cell 1, the two coupled lasers are reflected into the light absorber 7 by a 509nm total reflection mirror / 852nm anti-reflection 45° dichroic mirror to absorb excess coupled laser light and avoid stray light interference. After passing through the atomic gas cell 1, the two probe lasers are converted into electrical signals by photodetectors 10 (i.e., the first photodetector and the second photodetector) to output collectable response signals for dual-channel peak comparison and maximum value extraction.

[0029] Please see Figure 2 This is a schematic diagram of energy level transitions in a general four-level coherent coupling system. The probe laser couples the ground state |1> and the intermediate state |2>; the coupled laser couples the intermediate state |2> and the Rydberg state |3>; the local oscillator microwave field couples the Rydberg state |3> and the adjacent state |4> with the swept-frequency signal microwave field. Taking cesium atoms as an example, the four-level system based on cesium atoms in this example is as follows: an 852nm probe laser couples the ground state |1> and the intermediate state |2>; a 509nm coupled laser couples the intermediate state |2> and the Rydberg state |3>; the coupled laser can be detuned to optimize atomic coherence; the local oscillator microwave field and the microwave pulse signal to be measured are simultaneously coupled to the Rydberg state |3> and the adjacent Rydberg state |4>.

[0030] Please see Figure 3The figure shows the spectral response curves of the first and second signals of the dual-path detection using cesium atoms as an example. When the microwave pulse signal to be measured and the local oscillator microwave field simultaneously irradiate the atomic gas cell, the two detection beams will carry the transmission intensity changes related to the difference frequency signal, respectively. After the transmitted light is converted into an electrical signal by the photodetector, a dual-path superheterodyne signal containing the intermediate frequency component can be obtained, with instantaneous bandwidths of 6.1MHz and 26.7MHz, respectively.

[0031] Please see Figure 4 The figure shows the maximum response signal curve extracted after amplitude comparison of dual-channel detection using cesium atoms as an example. By comparing the amplitudes of the two signals and selecting the one with higher response intensity for processing, the superheterodyne signal with peak extraction can be obtained. Its instantaneous bandwidth is 34.5MHz, which effectively improves the response amplitude and signal-to-noise ratio of the microwave pulse signal.

[0032] according to Figure 3 and Figure 4 It is known that this invention improves the response of Rydberg atoms to microwave pulse signals by optimizing the optical path structure and enhancing the microwave field coupling efficiency. Through the single-cell dual-path collinear photoelectric optical path structure and dual-path peak comparison mechanism, the measured instantaneous bandwidth is extended from the maximum single-path 26.7MHz to 34.5MHz, thus achieving an effective improvement in the response bandwidth of microwave pulse signals.

[0033] Example 2 Based on Example 1, this example provides a superheterodyne detection method for optimizing the microwave pulse signal response of Rydberg atoms, implemented using the superheterodyne detection device of Example 1. (See [link to example 1]). Figure 5 The method includes the following steps: Step S1: Construct an atomic gas chamber 1 filled with alkali metal atomic vapor.

[0034] Step S2: The probe laser is divided into a first probe beam and a second probe beam, and the coupling laser is divided into a first coupling beam and a second coupling beam.

[0035] Step S3: The first probe light and the first coupling light enter the atomic gas chamber 1 in a collinear opposing manner, and the second probe light and the second coupling light enter the atomic gas chamber 1 in a collinear opposing manner.

[0036] Step S4: Radiation of the local oscillator microwave field and the frequency-scanning microwave signal to be measured to the atomic gas cell 1. The frequencies of the probe laser and the coupling laser are configured to create a four-level coherent system within the atomic gas cell 1: the probe laser couples the ground state |1> to the intermediate state |2>, the coupling laser couples the intermediate state |2> to the Rydberg state |3>, and the local oscillator microwave field and the microwave signal to be measured jointly couple the Rydberg state |3> to the adjacent Rydberg state |4>.

[0037] Step S5: Receive the first and second probe beams passing through the atomic gas chamber 1, and convert them into a first electrical signal and a second electrical signal.

[0038] Step S6: Perform spectrum analysis on the first electrical signal and the second electrical signal respectively to obtain the first response signal and the second response signal.

[0039] Specifically, the spectrum analysis includes: taking the difference frequency between the first electrical signal and the second electrical signal and the local oscillator microwave frequency to obtain the intermediate frequency signal, and the response signal is the amplitude of the intermediate frequency signal.

[0040] Step S7: Compare the amplitudes of the first response signal and the second response signal, and extract the response signal with the larger amplitude as the detection result.

[0041] It should be noted that the superheterodyne detection device and method for optimizing the microwave pulse signal response of Rydberg atoms in this invention are applicable to all atoms capable of Rydberg state transitions. In principle, alkali metal atoms, alkaline earth metal atoms, etc., can all be used in this invention, but in practice, cesium atoms are the optimal choice due to their stable energy level structure and easily tunable transition frequencies.

[0042] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in the present invention, and these modifications or substitutions should all be covered within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A superheterodyne detection device for optimizing the microwave pulse signal response of Rydberg atoms, characterized in that, include: Atomic gas chamber (1) is filled with atomic vapor that can be excited to the Rydberg state; A probe laser source, used to generate a probe laser; A coupled laser source, used to generate coupled laser light; The first beam splitting module is used to split the detection laser into a first detection beam and a second detection beam; The second beam splitting module is used to split the coupled laser into a first coupled beam and a second coupled beam. Local oscillator microwave source, used to generate local oscillator microwave field (3). A signal microwave source, used to generate the microwave signal to be tested for frequency scanning; A horn antenna (2) is used to radiate the local oscillator microwave field and the microwave signal to be measured to the atomic gas cell (1). The first photodetector is used to receive the first probe light passing through the atomic gas cell (1) and convert it into a first electrical signal; The second photodetector is used to receive the second probe light passing through the atomic gas cell (1) and convert it into a second electrical signal; The signal processing unit is connected to the first photodetector and the second photodetector respectively, and is used to perform spectrum analysis on the first electrical signal and the second electrical signal respectively to obtain the first response signal and the second response signal, and compare the amplitude of the first response signal and the second response signal to extract the response signal with the larger amplitude as the output. The optical path is configured such that the first probe light and the first coupling light enter the atomic gas cell (1) in a collinear opposing manner, and the second probe light and the second coupling light enter the atomic gas cell (1) in a collinear opposing manner.

2. The superheterodyne detection device for optimizing the microwave pulse signal response of Rydberg atoms according to claim 1, characterized in that, The frequencies of the probe laser and the coupling laser are configured to cause the atoms in the atomic gas chamber (1) to form a four-level coherent system: the probe laser couples the ground state |1> to the intermediate state |2>, the coupling laser couples the intermediate state |2> to the Rydberg state |3>, and the local oscillator microwave field and the microwave signal to be measured are coupled together to the Rydberg state |3> to the adjacent Rydberg state |4>.

3. The superheterodyne detection device for optimizing the microwave pulse signal response of Rydberg atoms according to claim 1, characterized in that, The first beam splitting module includes: An 852nm 45° semi-transparent and semi-reflective mirror (6) is used to divide the probe laser into a first path of reflected probe light and a second path of transmitted probe light; An 852nm 45° total reflection mirror (5) is used to reflect the second probe light parallel to the first probe light; The second beam splitting module includes: A 509nm semi-transparent and semi-reflective / 852nm anti-reflective 45° dichroic mirror (9) is highly reflective of the coupled laser wavelength and highly transparent of the probe laser wavelength, used to divide the coupled laser into a first path of reflected coupled light and a second path of transmitted coupled light. A 509nm total reflection / 852nm anti-reflection 45° dichroic mirror (8) is used to reflect the second coupled light into parallel light with the first coupled light. The first probe light and the first coupling light are collinearly opposed and enter the atomic gas chamber (1) along the same straight line, while the second probe light and the second coupling light are collinearly opposed and enter the atomic gas chamber (1) along another straight line.

4. The superheterodyne detection device for optimizing the microwave pulse signal response of Rydberg atoms according to claim 3, characterized in that, The 509nm semi-transparent / 852nm anti-reflective 45° dichroic mirror (9) is highly reflective of the coupled laser wavelength and highly transparent of the probe laser wavelength; the device also includes a light absorber (7) for absorbing the coupled laser reflected by the dichroic mirror.

5. The superheterodyne detection device for optimizing the microwave pulse signal response of Rydberg atoms according to claim 1, characterized in that, The atoms in the atomic vapor are cesium atoms or rubidium atoms.

6. The superheterodyne detection device for optimizing the microwave pulse signal response of Rydberg atoms according to claim 5, characterized in that, The atoms in the atomic vapor are cesium atoms, the wavelength of the detection laser is 852 nm, the wavelength of the coupling laser is 509 nm, and the ground state |1> is 6S. 1 / 2 The intermediate state |2> is 6P 3 / 2 .

7. The superheterodyne detection device for optimizing the microwave pulse signal response of Rydberg atoms according to claim 1, characterized in that, The signal processing unit includes a spectrum analysis unit and a comparator, which are used to perform spectrum analysis on the first electrical signal and the second electrical signal respectively to obtain an intermediate frequency signal, and compare the amplitude of the intermediate frequency signal to extract the one with the larger amplitude as the response signal.

8. The superheterodyne detection device for optimizing the microwave pulse signal response of Rydberg atoms according to claim 1, characterized in that, The frequency of the coupled laser source is tunable to optimize atomic coherence through detuning.

9. A superheterodyne detection method for optimizing the microwave pulse signal response of Rydberg atoms, characterized in that, Based on the superheterodyne detection device as described in any one of claims 1-8, the method includes the following steps: Construct an atomic gas chamber filled with alkali metal atomic vapor (1); The probe laser is divided into a first probe beam and a second probe beam, and the coupling laser is divided into a first coupling beam and a second coupling beam; The first probe light and the first coupling light are made to enter the atomic gas chamber (1) in a collinear opposing manner, and the second probe light and the second coupling light are made to enter the atomic gas chamber (1) in a collinear opposing manner. The local oscillator microwave field and the frequency-scanning microwave signal to be measured are radiated into the atomic gas cell (1); The frequencies of the probe laser and the coupling laser are configured to cause the atoms in the atomic gas chamber (1) to form a four-level coherent system: the probe laser couples the ground state |1> to the intermediate state |2>, the coupling laser couples the intermediate state |2> to the Rydberg state |3>, and the local oscillator microwave field and the microwave signal to be measured are coupled together to the Rydberg state |3> to the adjacent Rydberg state |4>. The first and second probe beams passing through the atomic gas cell (1) are received respectively and converted into a first electrical signal and a second electrical signal. Perform spectrum analysis on the first electrical signal and the second electrical signal respectively to obtain the first response signal and the second response signal; The amplitudes of the first response signal and the second response signal are compared, and the response signal with the larger amplitude is extracted as the detection result.

10. The superheterodyne detection method for optimizing the microwave pulse signal response of Rydberg atoms according to claim 9, characterized in that, The spectrum analysis includes performing spectrum analysis on the first electrical signal and the second electrical signal respectively to obtain an intermediate frequency signal, and the response signal is the amplitude of the intermediate frequency signal.

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