Multi-channel synchronous laser frequency locking device based on atomic reference

Abstract

The invention provides a multichannel synchronous laser frequency locking device based on atomic reference. The multichannel synchronous laser frequency locking device comprises an optical frequency locking module, a coupling light array module, a collimating and beam expanding group lens, an atomic gas chamber, a photoelectric detector array module and a dichroscope, detection light entering the atomic gas chamber parallelly penetrates through the atomic gas chamber and then is emitted to the photoelectric detector array module, multiple beams of coupling light emitted by the coupling light array module enter the dichroscope, and the multiple beams of coupling light reflected by the dichroscope parallelly enter the opposite direction of the detection light, penetrate through the atomic gas chamber and then are emitted to the collimation and beam expanding group lens. And the photoelectric detector array module converts an electromagnetic induction transparent spectrum signal in the detection light into an electric signal and corrects the frequency of the coupling light output by the coupling light array module in real time through a closed-loop feedback system. According to the invention, accurate frequency locking of multi-path coupling light can be realized, and the problem of complex multi-channel laser frequency locking structure in the prior art is solved.

Description

Technical Field

[0001] The present invention relates to the field of laser technology, and in particular to a multi-channel synchronous laser frequency locking device based on atomic reference. Background Art

[0002] Compared to traditional antennas, electric field measurement technology based on Rydberg atoms offers advantages such as high sensitivity, high selectivity, wide spectrum coverage, strong anti-interference capabilities, and high measurement accuracy. In Rydberg atom electric field measurement systems, the laser frequency-locking device is a core component ensuring measurement accuracy. Using optical feedback control, it locks the laser frequency to a reference frequency corresponding to a specific energy level transition of a Rydberg atom, providing a stable and precise frequency reference for atomic excitation. To meet the stringent requirements of localizing partial discharges and long-distance fiber optic transmission, current technology relies primarily on high-power lasers or multi-channel laser frequency-locking solutions.

[0003] High-power lasers utilize laser output exceeding 100mW to enhance atomic excitation efficiency and signal transmission distance. However, this approach has significant drawbacks: 1) Noise and energy loss: The spontaneous emission noise of high-power lasers increases exponentially with power, resulting in a significant amount of optical power being unavailable for atomic excitation; 2) Mode degradation risk: Semiconductor lasers are prone to mode hopping at high power, which reduces laser frequency stability and directly affects the accuracy of Rydberg atom excitation.

[0004] Multi-channel laser frequency locking schemes integrate multiple low-power lasers, using a single laser beam splitter to enter a saturated absorption spectroscopy (SAS) unit or an electromagnetically induced transparency (EIT) unit. A photodetector then generates a voltage signal, outputting a compensation voltage to the laser's piezoelectric ceramic (PZT) driver, thereby achieving laser locking. While this scheme can mitigate the drawbacks of high-power lasers, it places higher demands on the frequency synchronization accuracy of each channel (frequency detection error must be controlled within ±100kHz) and dynamic switching speed (sub-microseconds). Otherwise, multi-channel signal interference noise will result, reducing detection sensitivity. Furthermore, current multi-channel laser frequency locking schemes require each laser channel to be equipped with an independent optical reference cavity device, such as an atomic gas cell, lens assembly, and detector. This not only complicates the laser frequency locking structure and is costly, but also occupies a large system footprint, making it difficult to adapt to chip-based quantum devices. Therefore, how to integrate laser frequency locking devices to improve frequency synchronization accuracy and dynamic switching speed is a technical problem that needs to be solved. Summary of the Invention

[0005] The present invention provides a multi-channel synchronous laser frequency locking device based on atomic reference. By integrating the collimating beam expander group, atomic gas chamber and photodetector array module, it can not only achieve precise frequency locking of multi-channel coupled light, but also solve the problems of the existing technology of complex multi-channel laser frequency locking structure, high cost, large system footprint, and difficulty in meeting the needs of mobile quantum devices.

[0006] The technical solutions provided by the present invention are as follows: A multi-channel synchronous laser frequency locking device based on atomic reference includes an optical frequency locking module, a coupled light array module, a collimating beam expansion lens group, an atomic gas chamber, a photodetector array module, and a dichroic mirror.

[0007] The optical frequency locking module provides a frequency-locked detection light signal through the saturation absorption peak to achieve laser frequency stability.

[0008] The coupled light array module is used to generate a reverse-propagating control light field, forming a Λ-type energy level structure with the detection light, thereby inducing atomic quantum state coherence and generating an EIT window.

[0009] The collimating beam expanding mirror group is set on one side of the optical frequency locking module. The frequency-locked and beam-diverging detection light emitted by the optical frequency locking module is incident on the collimating beam expanding mirror group; the collimating beam expanding mirror group is used to expand the beam diameter of the detection light emitted by the optical frequency locking module, while optimizing the beam divergence angle. It can also be used to adapt to the action area of the atomic gas cell and improve the uniformity of the light-atom interaction.

[0010] The atomic gas chamber is arranged on one side of the collimating and expanding lens group. The detection light formed after the collimating and expanding lens group is emitted in parallel to the atomic gas chamber; the atomic gas chamber is used to provide cesium atomic vapor medium, and produces quantum coherence effect under the action of detection light and coupling light.

[0011] The photodetector array module is arranged on one side of the atomic gas chamber. The detection light incident on the atomic gas chamber passes through the atomic gas chamber in parallel and then exits the photodetector array module. The photodetector array module is used to convert the optical EIT transmission spectrum signal into an electrical signal, supports parallel data acquisition of multiple channels, and realizes the synchronous extraction of multi-channel frequency-locked error signals.

[0012] The dichroic mirror is arranged between the atomic gas chamber and the photodetector array module. The multiple coupling beams emitted by the coupling light array module are incident on the dichroic mirror. After being reflected by the dichroic mirror, the multiple coupling beams are incident in parallel in the opposite direction of the detection light and pass through the atomic gas chamber before being emitted to the collimating beam expansion group mirror; the dichroic mirror is used to reflect the coupling light of a specific wavelength and transmit the detection light of a specific wavelength, thereby realizing the spatial beam combining and reverse transmission control of the dual-wavelength light beams.

[0013] The photodetector array module converts the electromagnetically induced transparent spectrum signal in the detection light into an electrical signal and corrects the frequency of the coupled light output by the coupled light array module in real time through a closed-loop feedback system.

[0014] Preferably, the collimating and beam expanding lens assembly includes: The pinhole diaphragm is set between the optical frequency locking module and the atomic gas chamber. The detection light emitted by the optical frequency locking module is incident on the pinhole diaphragm and passes through the pinhole of the pinhole diaphragm. The pinhole diaphragm is used to filter out high-order mode stray light in the detection light path, greatly improving the cleanliness of the beam, reducing background noise, and ensuring frequency locking accuracy. The first convex lens is arranged between the pinhole aperture and the atomic gas chamber. The detection light after passing through the pinhole of the pinhole aperture is emitted to the first convex lens at a preset first divergence angle. The detection light formed after refraction by the first convex lens is incident in parallel into the atomic gas chamber.

[0015] Preferably, the collimating and beam expanding lens assembly further includes: a second convex lens, which is disposed between the optical frequency locking module and the pinhole aperture, and to which the detection light emitted by the optical frequency locking module at a preset second divergence angle is emitted; the second convex lens is used to convert the divergent light beam emitted by the optical frequency locking module into a parallel light beam; The third convex lens is arranged between the second convex lens and the pinhole aperture. The detection light shaped by the second convex lens is emitted in parallel to the third convex lens; it is refracted by the third convex lens and converged in the direction of the central axis of the third convex lens, incident on the pinhole of the pinhole aperture and forms a focus in the pinhole, and is emitted to the first convex lens at a preset first divergence angle; the third convex lens is used to amplify the beam diameter of the detection light and maintain the parallelism of the detection light.

[0016] Preferably, the mirror diameter of the second convex lens or the third convex lens is smaller than the mirror diameter of the first convex lens.

[0017] The present invention optimizes the beam collimation of the detection light and suppresses stray light through a collimating and beam expanding lens assembly to obtain a high signal-to-noise ratio detection light spectrum, and the EIT spectrum signal-to-noise ratio is improved by ≥20dB.

[0018] Preferably, the atomic gas chamber includes: The cesium atomic vapor chamber is arranged inside the atomic gas chamber. The detection light passing through the atomic gas chamber in parallel interacts coherently with the multi-beam coupling light emitted in the opposite direction, inducing an electromagnetically induced transparency effect in the cesium atomic vapor chamber. After the interaction, the cesium atomic vapor chamber emits the detection light to the photodetector array module.

[0019] Coherent interactions, including: Under the action of the probe light passing through the atomic vapor chamber in parallel, the cesium atoms filled in the cesium vapor chamber undergo energy level transition from the ground state to the first excited state; Under the action of parallel coupled light, the cesium atom undergoes energy level transition from the first excited state to the Rydberg state, wherein the principal quantum number of the cesium atom in the Rydberg state is greater than or equal to 50.

[0020] Preferably, the photodetector array module includes: Multiple photodetectors are arranged flush with the detection light action area. The detection light emitted from the cesium atomic vapor chamber is incident on the multiple photodetectors. The multiple photodetectors synchronously collect electromagnetically induced transparent spectrum signals and convert them into multi-channel electrical signals and send them to the coupled light array module.

[0021] The present invention forms multiple optical channels corresponding to multiple photodetectors and multiple coupled optical semiconductor lasers in a coupled optical array module, realizes frequency synchronization locking of the multiple optical channels through a closed-loop feedback system, and eliminates delay errors between channels.

[0022] Preferably, the closed-loop feedback system includes: A plurality of error signal extraction units are respectively connected to the plurality of photodetectors for calculating the peak position offset of the electromagnetically induced transparent spectrum signal in real time and outputting an error voltage; A plurality of PID control units are respectively connected to the plurality of error signal extraction units for processing the error voltage and outputting control voltage range data; A plurality of laser frequency real-time correction units are respectively communicated with a plurality of PID control units and are used to adjust the resonant cavity length of the coupled optical semiconductor laser through PZT piezoelectric ceramics according to control voltage range data.

[0023] The present invention achieves synchronous frequency locking of multi-channel lasers through the following steps: First, the probe light is initially frequency-locked using saturated absorption spectroscopy. The locked probe light then undergoes beam expansion through a collimating beam expander lens system to improve beam quality and adapt to subsequent optical path requirements. The expanded probe light then interacts with the array-type coupled light in a counter-propagation manner and enters a photodetector array, thereby obtaining a high signal-to-noise ratio electromagnetically induced transparency (EIT) spectrum. Finally, based on the EIT spectral signal, a closed-loop feedback system is used to precisely frequency-lock the multi-channel coupled light. This integrated design not only simplifies the complex structure of traditional multi-channel frequency locking but also significantly improves the system's anti-interference capability and frequency locking accuracy through the highly sensitive detection of Rydberg atoms.

[0024] The technical effects of the present invention are as follows: The multi-channel synchronous laser frequency locking device described in the present invention uses a collimating beam expander to expand the probe light beam, a single atomic gas chamber as a common frequency reference, and a photodetector array module to perform electromagnetically induced transparency (EIT) spectral signal detection on multiple probe light beams. This device breaks through the limitations of traditional single-channel frequency locking, thereby achieving parallel frequency locking of multiple lasers. This solves the problems of the existing technology, such as the complex multi-channel laser frequency locking structure and the inability of a single-channel architecture to achieve synchronous locking of multiple laser frequencies. The present invention uses miniaturized Rydberg atom sensing units such as a collimating beam expander, a single atom gas chamber, and a photodetector array module to support direct coupling with an optical fiber array. This reduces the system footprint by more than 60% and compresses the total optical path length to less than 0.5m, solving the problem of the system's large footprint and difficulty meeting the needs of mobile quantum devices. The present invention uses a collimating beam expander to filter out high-order transverse mode light, thereby improving the EIT signal-to-noise ratio from 20dB to a range greater than or equal to 43dB, and compressing the error to a range less than 1kHz. This solves the problem of low EIT signal-to-noise ratio, which leads to a frequency detection error of ±300kHz. This directly reflects the problem of insufficient frequency locking accuracy of existing multi-channel laser frequency locking devices and their inability to meet the stability requirements of scenarios such as atomic clocks.

[0025] The present invention replaces the open-loop control in the prior art with a real-time closed-loop feedback system, thereby reducing the frequency drift error by 90%. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is a structural schematic diagram of a multi-channel synchronous laser frequency locking device based on atomic reference according to an embodiment of the present invention. In the figure, 1 is the second convex lens, 2 is the second convex lens, 3 is the pinhole aperture, 4 is the first convex lens, and 5 is the dichroic mirror. DETAILED DESCRIPTION

[0027] In order to enable those skilled in the art to better understand the technical solutions in this application, the following will clearly and completely describe the technical solutions in the embodiments of this application in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of this application.

[0028] As attached Figure 1 As shown, an embodiment of the present invention provides a multi-channel synchronous laser frequency locking device based on atomic reference, including an optical frequency locking module, a coupling light array module, a collimating and expanding lens assembly, an atomic gas chamber, a photodetector array module and a dichroic mirror 5.

[0029] The optical frequency locking module is used to perform frequency locking using saturated absorption spectroscopy (SAS) technology, outputting frequency-stable probe light to the collimating and beam expanding mirror assembly.

[0030] The collimating and expanding lens assembly is positioned to the right of the optical frequency-locking module. The frequency-locked and divergent probe light emitted by the optical frequency-locking module is incident on the collimating and expanding lens assembly. The frequency-locked probe light is then expanded and collimated by the collimating and expanding lens assembly, improving the parallelism and spot size of the probe light beam and adapting to subsequent multi-channel optical path requirements. In this embodiment, the collimating and expanding lens assembly comprises a second convex lens 1, a second convex lens 2, a pinhole aperture 3, and a first convex lens 4. The probe light emitted by the optical frequency-locking module at a preset second divergence angle is emitted by the second convex lens 1. After being shaped by the second convex lens 1, the probe light is emitted parallel to the second convex lens 2. It is refracted by the second convex lens 2 and converges toward the central axis of the second convex lens 2, entering the pinhole of the pinhole aperture 3. After passing through the pinhole, it is emitted at the preset first divergence angle to the first convex lens 4. The probe light refracted by the first convex lens 4 is incident parallel to the atomic gas chamber.

[0031] In the process of collimating and expanding the detection light by the collimating and expanding lens group, a second divergence angle is preset, preferably 5mrad; the focal length of the second convex lens 1 is smaller than the focal length of the second convex lens 2, the focal length of the second convex lens 1 is preferably 30mm, and the focal length of the second convex lens 2 is preferably 60mm. The second convex lens 1 and the second convex lens 2 are used for the preliminary collimation of the detection light, and the output characteristics are preliminary collimated beams, and the beam diameter is expanded to twice the original beam diameter; the pinhole aperture 3 is mainly used to filter out high-order transverse mode stray light and block non-parallel beams. The pinhole is located at the focus of the second convex lens 2. When the detection light is pinhole filtered, the pinhole aperture is preferably 0.5mm, and the output characteristics are that the Gaussian mode purity is greater than 9 5%; the light beam after the pinhole is incident on the first convex lens 4, wherein the focal length of the first convex lens 4 is greater than the focal length of the second convex lens 1 or the second convex lens 2, and the focal length of the first convex lens 4 is preferably 120 mm. The first convex lens 4 further expands the preliminary collimated light, and the expansion multiple is 2 times, and the divergence angle is optimized to less than 0.1 mrad. Finally, after the expansion by the first convex lens 4, the total output detection light beam diameter is 4 times the original beam diameter. In summary, the detection light is collimated and expanded by the collimating and expanding group mirrors in this embodiment, which can expand the beam diameter of the detection light to more than 4 times, and the divergence angle is increased to less than 0.1 mrad, thereby matching the atomic gas chamber and improving the EIT signal-to-noise ratio.

[0032] The atomic gas chamber is arranged on one side of the collimating and expanding lens group, and the detection light formed after the collimating and expanding lens group is collimated is emitted in parallel to the atomic gas chamber; the atomic gas chamber includes a cesium atomic vapor chamber, which is arranged inside the atomic gas chamber, and the detection light passing through the atomic gas chamber in parallel and the multi-beam coupling light emitted in the opposite direction undergoes coherent interaction. The coherent interaction is that under the action of the detection light with a wavelength greater than or equal to 852.00nm passing through the atomic gas chamber in parallel, the cesium atoms filled in the cesium atomic vapor chamber undergo energy level transition from the ground state to the first excited state; under the action of the coupling light with a wavelength greater than or equal to 509.00nm emitted in parallel, the cesium atoms undergo energy level transition from the first excited state to the Rydberg state, wherein the principal quantum number of the cesium atoms in the Rydberg state is greater than or equal to 50; an electromagnetic induced transparency effect is induced in the cesium atomic vapor chamber, and after the interaction, the cesium atomic vapor chamber emits the detection light to the photodetector array module.

[0033] A photodetector array module is provided on one side of the atomic gas chamber. The detection light incident on the atomic gas chamber passes through the atomic gas chamber in parallel and then exits the photodetector array module. The photodetector array module includes multiple photodetectors, preferably 2*2 in this embodiment. The four photodetectors are arranged flush with the detection light action area. The detection light emitted from the cesium atomic vapor chamber is incident on the four photodetectors. The four photodetectors synchronously collect electromagnetically induced transparent spectrum signals and convert them into four electrical signals and send them to the coupled light array module.

[0034] The dichroic mirror 5 is arranged between the atomic gas chamber and the photodetector array module. The multiple coupling beams emitted by the coupling light array module are incident on the dichroic mirror 5. After being reflected by the dichroic mirror 5, the multiple coupling beams are incident in parallel with the relative direction of the detection light and pass through the atomic gas chamber before being emitted to the collimating beam expander group mirror.

[0035] The photodetector array module converts the electromagnetically induced transparent spectrum signal in the detection light into an electrical signal and performs real-time correction on the frequency of the coupled light output by the coupled light array module through a closed-loop feedback system. Preferably, the closed-loop feedback system includes multiple error signal extraction units, multiple PID control units, and multiple laser frequency real-time correction units. In this embodiment, there are preferably four error signal extraction units, which are respectively communicated with the photodetectors for real-time calculation of the peak position offset of the electromagnetically induced transparent spectrum signal and output of the error voltage. There are preferably four PID control units, which are respectively communicated with the four error signal extraction units for processing the error voltage and outputting control voltage range data. There are preferably four laser frequency real-time correction units, which are respectively communicated with the four PID control units for adjusting the resonant cavity length of the coupled light semiconductor laser through PZT piezoelectric ceramics according to the control voltage range data.

[0036] An embodiment of the present invention further provides a multi-channel synchronous laser frequency locking method applied to the multi-channel synchronous laser frequency locking device, comprising the following steps: S01. The optical frequency locking module uses saturated absorption spectroscopy (SAS) technology to frequency-lock the detection light output by the detection light semiconductor laser, and then outputs the detection light with stable frequency to the collimating and beam expanding mirror assembly.

[0037] S02. The detection light shaped by the second convex lens in the collimating beam expander is emitted in parallel to the third convex lens, then refracted by the third convex lens and converged toward the central axis of the third convex lens, entering the pinhole of the pinhole aperture, passing through the pinhole and emitting to the first convex lens at a preset first divergence angle. The detection light formed after refraction by the first convex lens is incident in parallel to the atomic gas chamber.

[0038] S03. The multiple coupling beams emitted by the coupling light array module are incident on the dichroic mirror. After being reflected by the dichroic mirror, the multiple coupling beams are incident on the atomic gas chamber in parallel with the direction opposite to the detection light.

[0039] S04. The detection light passing through the atomic gas chamber in parallel interacts coherently with the multiple coupling beams incident in the opposite direction, inducing an electromagnetically induced transparency effect in the cesium atomic vapor chamber. After the interaction, the atomic gas chamber emits the detection light to the photodetector array module.

[0040] S05. The four photodetectors in the photodetector array module synchronously collect electromagnetically induced transparent spectrum signals and convert them into four electrical signals, which are sent to the coupled light array module through a closed-loop feedback system.

[0041] In this embodiment of the present invention, an optical frequency-locking module is first used to perform preliminary frequency locking of the probe light using saturation absorption spectroscopy. The locked probe light is then expanded by a collimating beam-expanding lens group to improve beam quality and adapt to subsequent optical path requirements. The expanded probe light then interacts with the array-type coupled light in a reverse transmission manner and enters the photodetector array, thereby obtaining an electromagnetically induced transparency (EIT) spectrum with a high signal-to-noise ratio. Finally, based on the EIT spectral signal, a closed-loop feedback system is used to achieve precise frequency locking of the multi-channel coupled light. This integrated design not only simplifies the complex structure of traditional multi-channel frequency locking but also significantly improves the system's anti-interference capability and frequency-locking accuracy through the highly sensitive detection of Rydberg atoms.

Claims

1. A multi-channel synchronous laser frequency locking device based on atomic reference, comprising an optical frequency locking module and a coupled light array module, characterized in that: Also included are: A collimating beam expanding lens assembly is provided on one side of the optical frequency locking module, and the detection light emitted by the optical frequency locking module, which is frequency locked and has a divergent beam, is incident on the collimating beam expanding lens assembly; An atomic gas chamber is provided on one side of the collimating and beam expanding lens assembly, and the detection light formed after the beam expansion and collimation by the collimating and beam expanding lens assembly is emitted in parallel to the atomic gas chamber; A photodetector array module is provided on one side of the atomic gas chamber, and the detection light incident on the atomic gas chamber passes through the atomic gas chamber in parallel and then exits the photodetector array module; A dichroic mirror, wherein the dichroic mirror is arranged between the atomic gas chamber and the photodetector array module, the multiple coupling beams emitted by the coupling light array module are incident on the dichroic mirror, and the multiple coupling beams after being reflected by the dichroic mirror are incident in parallel with the opposite direction of the detection light and pass through the atomic gas chamber before being emitted to the collimating beam expansion group mirror; The photodetector array module converts the electromagnetically induced transparent spectrum signal in the detection light into an electrical signal and corrects the frequency of the coupled light output by the coupled light array module in real time through a closed-loop feedback system.

2. A multi-channel synchronous laser frequency locking device based on atomic reference according to claim 1, characterized in that: The collimating and beam expanding lens assembly includes: A pinhole aperture is provided between the optical frequency locking module and the atomic gas chamber, and the detection light emitted by the optical frequency locking module is incident on the pinhole aperture and passes through the pinhole of the pinhole aperture; The first convex lens is arranged between the pinhole aperture and the atomic gas chamber. The detection light after passing through the pinhole of the pinhole aperture is emitted to the first convex lens at a preset first divergence angle, and the detection light formed after refraction by the first convex lens is incident in parallel into the atomic gas chamber.

3. The multi-channel synchronous laser frequency locking device based on atomic reference according to claim 2, characterized in that: The collimating and beam expanding lens assembly also includes: a second convex lens, wherein the second convex lens is arranged between the optical frequency locking module and the pinhole aperture, and the detection light emitted by the optical frequency locking module at a preset second divergence angle is emitted to the second convex lens; The third convex lens is arranged between the second convex lens and the pinhole aperture. The detection light shaped by the second convex lens is emitted in parallel to the third convex lens; it is refracted by the third convex lens and converges in the direction of the central axis of the third convex lens, enters the pinhole of the pinhole aperture and forms a focus in the pinhole, and is emitted to the first convex lens at a preset first divergence angle.

4. The multi-channel synchronous laser frequency locking device based on atomic reference according to claim 3, characterized in that: The mirror diameter of the second convex lens or the third convex lens is smaller than the mirror diameter of the first convex lens.

5. A multi-channel synchronous laser frequency locking device based on atomic reference according to claim 1 or 4, characterized in that: The atomic gas chamber includes: The cesium atomic vapor chamber is arranged inside the atomic gas chamber. The detection light passing through the atomic gas chamber in parallel interacts coherently with the multi-beam coupling light emitted in the opposite direction, inducing an electromagnetically induced transparency effect in the cesium atomic vapor chamber. After the interaction, the cesium atomic vapor chamber emits the detection light to the photodetector array module; Coherent interactions, including: Under the action of the probe light passing through the atomic vapor chamber in parallel, the cesium atoms filled in the cesium vapor chamber undergo energy level transition from the ground state to the first excited state; Under the action of parallel coupled light, the cesium atom undergoes energy level transition from the first excited state to the Rydberg state, wherein the principal quantum number of the cesium atom in the Rydberg state is greater than or equal to 50.

6. The multi-channel synchronous laser frequency locking device based on atomic reference according to claim 5, characterized in that: The photodetector array module includes: Multiple photodetectors are arranged flush with the detection light action area. The detection light emitted by the cesium atomic vapor chamber is incident on the multiple photodetectors. The multiple photodetectors synchronously collect electromagnetically induced transparent spectrum signals and convert them into multi-channel electrical signals and send them to the coupled light array module.

7. A multi-channel synchronous laser frequency locking device based on atomic reference according to claim 1 or 6, characterized in that: The closed-loop feedback system includes: A plurality of error signal extraction units are respectively connected to the plurality of photodetectors for calculating the peak position offset of the electromagnetically induced transparent spectrum signal in real time and outputting an error voltage; A plurality of PID control units are respectively connected to the plurality of error signal extraction units for processing the error voltage and outputting control voltage range data; A plurality of laser frequency real-time correction units are respectively communicated with a plurality of PID control units and are used to adjust the resonant cavity length of the coupled optical semiconductor laser through PZT piezoelectric ceramics according to control voltage range data.

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