A reflective single-beam dual-axis atomic spin gyroscope

Abstract

A reflective single-beam biaxial atomic spin gyroscope. A beam of elliptically polarized light is incident on an atomic gas cell to pump alkali metal atoms and inert gas nucleons to make them reach a polarized state. At the same time, a rotating modulation magnetic field is applied in a direction perpendicular to the pumping direction to modulate the electron polarization vector in the pumping direction and carry rotation information. The pumping light exiting the atomic gas cell is reflected by a mirror, passes through the atomic gas cell again, and finally enters a balanced differential module and realizes the extraction of rotation signals through a phase-locked amplifier signal acquisition module and decouples biaxial inertial signals by adjusting the phase shift of the reference signal. This is beneficial to the development of miniaturized SERF atomic spin gyroscopes, beneficial to enhancing the optical rotation angle signal, improving the signal-to-noise ratio and system sensitivity, and beneficial to improving the practicality of the gyroscope.

Description

Technical Field

[0001] The present invention relates to the technical field of atomic spin gyroscopes, in particular to a reflective single-beam biaxial atomic spin gyroscope. An elliptically polarized light is incident on an atomic gas cell to pump alkali metal atoms and noble gas nucleons to make them reach a polarized state. At the same time, a rotating modulation magnetic field is applied in a direction perpendicular to the pumping direction to modulate the electron polarization vector in the pumping direction and carry rotation information. The pumping light exiting the atomic gas cell is reflected by a mirror, passes through the atomic gas cell again, and finally enters a balanced differential module and realizes the extraction of rotation signals through a phase-locked amplifier signal acquisition module and decouples biaxial inertial signals by adjusting the phase shift of a reference signal, which is beneficial to the development of miniaturized SERF atomic spin gyroscopes, beneficial to enhancing the optical rotation angle signal, improving the signal-to-noise ratio and system sensitivity, and beneficial to improving the practicality of gyroscopes. Background Art

[0002] Navigation technology plays a crucial role in the national economic development. Gyroscopes are the key part of inertial guidance and the key factor affecting the performance of navigation systems. With the continuous development of quantum control technology, atomic inertial measurement instruments have become an important development direction of the new generation of inertial measurement instruments. Among them, SERF atomic spin gyroscopes have received extensive attention from scholars at home and abroad due to their ultra-high ultimate precision.

[0003] However, the current SERF atomic spin gyroscopes mainly adopt a signal extraction scheme of pumping-detection, which requires at least two complete laser systems, greatly increasing the volume of the gyroscope system and being not conducive to the miniaturization and integration of the gyroscope. On the other hand, SERF gyroscopes using two beams have strict requirements for the optical path orthogonality in installation. In actual operation, due to installation errors, the sensitivity and long-term stability of signal output decrease, which also affects the actual use. In addition, the output signal is related to the length of the interaction between light and atoms passing through the gas cell, and the measurement effect of the scheme of the light beam passing through the gas cell once will be limited. Summary of the Invention

[0004] In view of the deficiencies in the prior art, the present invention proposes a reflective single-beam dual-axis atomic spin gyroscope. A beam of elliptically polarized light is incident on an atomic gas cell to pump alkali metal atoms and inert gas nucleons to make them reach a polarized state. At the same time, a rotating modulation magnetic field is applied in a direction perpendicular to the pumping direction to modulate the electron polarization vector in the pumping direction and carry rotational information. The pumping light emerging from the atomic gas cell is reflected by a mirror, passes through the atomic gas cell again, and finally enters a balanced differential module. The rotational signal is extracted through a lock-in amplifier signal acquisition module, and the dual-axis inertial signal decoupling is achieved by adjusting the phase shift of the reference signal, which is beneficial to the development of a miniaturized SERF atomic spin gyroscope, beneficial to enhancing the optical rotation angle signal, improving the signal-to-noise ratio and system sensitivity, and beneficial to improving the practicality of the gyroscope.

[0005] The technical solution of the present invention is as follows:

[0006] A reflective single-beam dual-axis atomic spin gyroscope, characterized in that it includes a first pumping beam incident on an atomic gas cell in the positive z-axis direction and a second pumping beam incident on the atomic gas cell in the negative z-axis direction. The second pumping beam is a reflected beam formed by reflecting the first pumping beam after it emerges from the atomic gas cell by a mirror. The second pumping beam is reflected from the reflection side of an unpolarized beam splitter prism to a photoelectric detection balanced differential detection module after emerging from the atomic gas cell. The photoelectric detection balanced differential detection module transmits a differential signal to a lock-in amplifier signal acquisition module, and the lock-in amplifier signal acquisition module collects a rotational signal and achieves dual-axis inertial signal decoupling by adjusting the phase shift of a reference signal.

[0007] The first pumping beam comes from a laser, and the laser is connected to the atomic gas cell through a first half-wave plate, a first polarization beam splitter prism, a first polarizer, a liquid crystal phase retarder, a second polarizer, a second half-wave plate, a Glan-Taylor prism, a quarter-wave plate, and the unpolarized beam splitter prism connected in series in sequence.

[0008] The reflection side of the first polarization beam splitter prism is connected to a frequency stabilization module, the frequency stabilization module is connected to the laser, the reflection side of the Glan-Taylor prism is connected to a pumping laser light intensity stabilization circuit, and the pumping laser light intensity stabilization circuit is connected to the liquid crystal phase retarder.

[0009] The photoelectric detection balanced differential detection module includes a first photodetector and a second photodetector respectively connected to the lock-in amplifier signal acquisition module. The first photodetector is connected to the transmission side of a second polarization beam splitter prism, the second photodetector is connected to the reflection side of the second polarization beam splitter prism, and the input side of the second polarization beam splitter prism is connected to the reflection side of the unpolarized beam splitter prism through a third half-wave plate.

[0010] An oven, a three-axis coil, and a magnetic shielding layer are sequentially arranged outward around the atomic gas cell.

[0011] The atomic gas cell is filled with an alkali metal, an inert gas, and a quenching gas.

[0012] The phase shift of the adjustment reference signal includes inputting a fixed angular rate in the y direction through a high-precision turntable to adjust the phase shift φ of the demodulation reference signal. When the demodulation signal is no longer sensitive to the angular rate in the y direction, the system output channel corresponding to this phase shift is defined as the first output channel CH1, and this channel is only sensitive to the rotational input in the x direction; the demodulation phase of the other output channel is φ + 90°, and the system output channel corresponding to this phase shift is defined as the second output channel CH2, and this channel is only sensitive to the rotational input in the y direction, completing the decoupling of the biaxial signals.

[0013] The decoupling of the biaxial inertial signals includes that the phase shift φ output by the first output channel CH1 is determined by zeroing the coupling response of the rotational input in the y direction, and the specific phase shift of the second output channel CH2 is determined according to the rotational coupling response of zeroing the x direction.

[0014] The operation of the gyroscope includes the following steps:

[0015] Step 1, install the reflective single-beam biaxial atomic spin gyroscope on the carrier platform, turn on the heating system, perform precise magnetic field compensation on the residual magnetism in the shielding system, and perform optical pumping on the atomic ensemble. For the convenience of explaining the principle, we define the z direction as the propagation direction when the pumping light first enters the atomic gas cell, define the direction of the gyroscope pointing to the sky as the y direction, and the x direction can be obtained through the right-hand rule;

[0016] Step 2, apply a rotating modulation magnetic field on the plane perpendicular to the pumping light where B m is the amplitude of the rotating modulation magnetic field, ω is the angular frequency of the rotating modulation magnetic field, and are the unit vectors in the x and y directions. This rotating modulation magnetic field modulates the electron spin, enabling the rotational information to be modulated to a high frequency for signal extraction;

[0017] Step 3, after the pumping beam first exits the gas cell, adjust the position and direction of the mirror so that the beam is reflected by the mirror and passes through the gas cell again, doubling the length of interaction with the atoms and correspondingly increasing the signal intensity, which can effectively increase the signal-to-noise ratio;

[0018] Step 4, after the system signal is stable, apply a z-direction compensation magnetic field using the three-axis magnetic field coil to adjust the gyroscope to the nuclear spin self-compensation state, enabling it to have the ability to resist environmental low-frequency magnetic noise fluctuations;

[0019] Step 5: The reflected pumping beam changes its propagation direction through a non-polarizing beam splitter prism and enters the balanced differential detection module. The signal acquisition module of the lock-in amplifier demodulates the first-harmonic signal in the optical intensity signal, and the voltage response signal generated by the rotational input is extracted.

[0020] Step 6: A fixed angular rate in the y direction is input through a high-precision turntable to adjust the phase shift φ of the demodulation reference signal. When the demodulated signal is no longer sensitive to the angular rate in the y direction, the system output channel corresponding to this phase shift is defined as the first output channel CH1, which is only sensitive to the rotational input in the x direction; the demodulation phase of the other output channel is φ + 90°, and the system output channel corresponding to this phase shift is defined as the second output channel CH2, which is only sensitive to the rotational input in the y direction, completing the decoupling of the two-axis signals.

[0021] Step 7: Different angular rates are sequentially input through the high-precision turntable, and the corresponding voltage signal responses are collected, thereby calibrating the relationship between the voltage signal and the rotational input, obtaining the rotational scale factor, completing the calibration, and starting to be used.

[0022] The technical effects of the present invention are as follows: Compared with the prior art, a reflective single-beam two-axis atomic spin gyroscope of the present invention can simultaneously complete optical pumping and two-axis inertial measurement with only one beam of light, which is beneficial to the development of miniaturized SERF atomic spin gyroscopes. The setting that the beam of the gyroscope passes through the atomic cell twice is beneficial to enhancing the optical rotation angle signal, improving the signal-to-noise ratio and the system sensitivity. The gyroscope realizes the decoupling of two-axis inertial signals, which is beneficial to improving the practicability of the gyroscope.

[0023] In a reflective single-beam two-axis atomic spin gyroscope of the present invention, for the pumping light passing through the atomic cell twice, the rotational signal carried in the polarization state of the light is enhanced twice. Compared with a common single-beam gyroscope passing through the atomic cell once, it can effectively improve the intensity of the useful signal, realizing the improvement of the signal-to-noise ratio and the inertial sensitivity. When obtaining the rotational signal through the signal acquisition module of the lock-in amplifier, we demodulate the first-harmonic component in the optical signal. By the method described in Step 6, by adjusting the phase of the demodulation reference signal, the independent output of the two channels for the signals of the measurement axes in the x and y directions is realized, achieving the decoupling of the two-axis signals. This decoupling method improves the practicability of the gyroscope and lays a solid foundation for the future miniaturized and practical atomic spin gyroscope. Description of the Drawings

[0024] Figure 1 It is a schematic structural diagram of a reflective single-beam two-axis atomic spin gyroscope.

[0025] The reference numerals are listed as follows: A1 - laser; A2 - first half-wave plate; A3 - first polarization beam splitter prism; A4 - first polarizer; A5 - liquid crystal phase retarder; A6 - second polarizer; A7 - second half-wave plate; A8 - Glan-Taylor prism; A9 - quarter-wave plate; A10 - mirror; A11 - non-polarizing beam splitter prism; A12 - third half-wave plate; A13 - second polarization beam splitter prism; A14 - first photodetector; A15 - second photodetector; B1 - frequency stabilization module; B2 - pump laser intensity stabilization system; B3 - lock-in amplifier signal acquisition module; C1 - atomic gas cell; C2 - oven; C3 - three-axis coil; C4 - magnetic shielding layer. Detailed implementation manners

[0026] The present invention will be described below in conjunction with the accompanying drawings ( Figure 1 ). and embodiments.

[0027] Figure 1 is a schematic structural diagram of a reflective single-beam two-axis atomic spin gyroscope. Refer to Figure 1 As shown, the reflective single-beam two-axis atomic spin gyroscope uses a beam of elliptically polarized light to enter the atomic gas cell, so that alkali metal atoms and inert gas nucleons are pumped and enter the polarized state. At the same time, a rotating modulation magnetic field perpendicular to the pumping direction is applied to modulate the electron polarization vector and make the electron spin component in the pumping direction carry the rotation information. The pumped light exiting the gas cell is reflected by a mirror, passes through the atomic gas cell again, and finally enters the balanced differential module, and a first-harmonic signal is demodulated by a lock-in amplifier to complete the extraction and output of the rotation signal. This gyroscope can simultaneously complete optical pumping and two-axis inertial measurement with only one beam of light, laying a foundation for the development of a miniaturized SERF atomic spin gyroscope. The arrangement of the atomic gas cell for the light beam enhances the optical rotation angle signal, improves the signal-to-noise ratio, and improves the system sensitivity. By adjusting the phase shift of the reference signal, a decoupling method for two-axis inertial signals is proposed, improving the practicality of the atomic gyroscope.

[0028] A reflective single-beam two-axis atomic spin gyroscope specifically includes the following parts:

[0029] The core sensitive systems therein include an atomic gas cell C1, an oven C2, a three-axis coil C3, and a magnetic shielding layer C4. The atomic gas cell C1 contains alkali metal droplets of potassium atoms and rubidium atoms for providing electron spin. Additionally, it also includes nitrogen gas and the inert gas neon 21. The oven C2 is wrapped by a thin-film heating resistor sheet to achieve temperature heating. A PT1000 platinum resistor is used to collect the heating temperature, which is combined with the circuit system to achieve temperature control. The three-axis coil C3 is used to provide bias magnetic fields and rotational modulation magnetic fields in three orthogonal directions to compensate for remanent magnetism and modulate electron spin. The magnetic shielding layer C4 is composed of three layers of permalloy and one layer of manganese-zinc ferrite. It functions to shield the ambient magnetic field and provide a near-zero magnetic field, which is a necessary condition for the atomic spin to achieve a spin-exchange relaxation-free state and is the basis for achieving high-precision inertial measurement.

[0030] The optical system therein includes: an optical system composed of a laser A1, a first 1 / 2 wave plate A2, a first polarization beam splitter prism A3, a first polarizer A4, a liquid crystal phase retarder A5, a second polarizer A6, a second 1 / 2 wave plate A7, a Glan-Taylor prism A8, a 1 / 4 wave plate A9, a mirror A10, a non-polarizing beam splitter prism A11, a third 1 / 2 wave plate A12, a second polarization beam splitter prism A13, a first photodetector A14, a second photodetector A15, a frequency stabilization module B1, and a pump laser light intensity stabilization system B2. All components of the optical system should be coaxial. Among them, the pump laser exits from the laser A1, and after passing through the first 1 / 2 wave plate A2 and the first polarization beam splitter prism A3, the first polarization is achieved. Part of the main path laser is reflected by the first polarization beam splitter prism A3 to the bypass path and enters the frequency stabilization module B1 to achieve frequency locking of the pump laser, which is stabilized at the D1 line of potassium atoms. The pump laser on the main path continues to propagate, and after passing through the first polarizer A4, the liquid crystal phase retarder A5, the second polarizer A6, the second 1 / 2 wave plate A7, the Glan-Taylor prism A8, and the pump laser light intensity stabilization system B2, the stable control of the main path light intensity is achieved. The pump laser with stable light intensity and frequency is converted into elliptically polarized light by the 1 / 4 wave plate A9 and continues to propagate through the non-polarizing beam splitter prism A11 and is incident into the atomic gas cell C1. The first-emitted pump light passes through the mirror A10 and propagates in the opposite direction and enters the atomic gas cell C1 again. The pump light emitted again changes its propagation direction through the non-polarizing beam splitter prism A11 and enters the balanced differential detection module composed of the third 1 / 2 wave plate A12, the second polarization beam splitter prism A13, the first photodetector A14, and the second photodetector A15 to obtain the light intensity signal. The collected light intensity signal is used by the lock-in amplifier signal acquisition module B3 to extract the rotation signal.

[0031] A method for using a reflective single-beam two-axis atomic spin gyroscope includes the following steps:

[0032] Step 1: Install the SERF atomic spin gyroscope on the carrier platform, turn on the heating system, precisely compensate the residual magnetism in the shielding system with a magnetic field, and perform optical pumping on the atomic ensemble. For the convenience of explaining the operation method, we define the z-direction as the propagation direction when the pumping light first enters the atomic gas cell, the direction in which the gyroscope points to the sky as the y-direction, and the x-direction can be obtained by the right-hand rule.

[0033] Step 2: Apply a rotating modulation magnetic field in the plane perpendicular to the pumping light. where B n is the amplitude of the rotating modulation magnetic field, ω is the angular frequency of the rotating modulation magnetic field, and are the unit vectors in the x- and y-directions. This rotating modulation magnetic field modulates the electron spin, enabling the rotational information to be modulated to a high frequency for subsequent signal extraction. Generally, B m is in the range of 100 ± 10 nT, ω is in the range of 6280 ± 1256 rad / s, and the specific values of the two are adjusted comprehensively to maximize the peak-to-peak value of the modulation signal.

[0034] Step 3: After the pumping beam exits the gas cell for the first time, adjust the position and direction of the mirror A10 so that the beam is reflected by the mirror and passes through the gas cell again, doubling the length of interaction with the atoms and correspondingly increasing the signal intensity, which can effectively increase the signal-to-noise ratio.

[0035] Step 4: After the system signal stabilizes, apply a z-direction compensation magnetic field using the three-axis magnetic field coil, and adjust the gyroscope to the nuclear spin self-compensation state to endow it with the ability to resist environmental low-frequency magnetic noise fluctuations.

[0036] Step 5: The reflected pumping beam changes its propagation direction by the non-polarizing beam splitter prism and enters the balanced differential detection module. The lock-in amplifier signal acquisition module demodulates the first-harmonic signal in the optical intensity signal to extract the voltage response signal generated by the rotational input.

[0037] Step 6: Input a fixed angular rate of 0.1° / s in the y-direction through the high-precision turntable, and adjust the phase shift φ of the demodulation reference signal. When the demodulation signal is no longer sensitive to the angular rate in the y-direction, define the system output channel corresponding to this phase shift as the first output channel CH1, which is only sensitive to the rotational input in the x-direction; the demodulation phase of the other output channel is φ + 90°, and define the system output channel corresponding to this phase shift as the second output channel CH2, which is only sensitive to the rotational input in the y-direction, thus completing the decoupling of the two-axis signals.

[0038] Step 7: Input angular rates from -0.1° / s to 0.1° / s in sequence through a high-precision turntable, with a step size of 0.01° / s, and collect the corresponding voltage signal responses, so as to calibrate the relationship between the voltage signal and the rotational input, obtain the rotational scale factor, complete the calibration and start to be used.

[0039] The specific principle of this scheme is explained below through formula derivation. When the gyroscope enters the normal operating state, during inertial rotation, the first harmonic component of the electron spin along the z direction can be expressed in the following form:

[0040]

[0041] where

[0042]

[0043]

[0044]

[0045]

[0046] where Ω x and Ω y are the angular rate inputs in the x and y directions, ω is the angular frequency of the rotating modulation magnetic field; γ e and γ n are the gyromagnetic ratios of the electron spin and the nuclear spin; B e and B n are the equivalent magnetic fields generated by the electron spin and the nuclear spin respectively; is the steady-state DC component of the electron spin along the z direction; J0(u) and J1(u) are the Bessel functions of the first kind of order 0 and order 1, and the parameter u is defined as u = γ e B m / (Qω), where B m is the amplitude of the rotating modulation magnetic field, and Q is the slowdown factor; and are the total relaxations corresponding to the electron spin and the nuclear spin respectively. A, B, Γ1, Γ2 are intermediate variables, and t is time.

[0047] After the pumping light exits the atomic gas cell C1 and is incident on the reflecting mirror A10, it is reflected and then incident on the atomic gas cell again, and propagates in the reverse direction. After being reflected by the non-polarizing beam splitter prism A11, the direction is changed, and finally the light intensity signal I to be demodulated is obtained through the balanced differential module. The expression is as follows

[0048]

[0049] Among them, I0 is the light intensity coefficient, c is the speed of light, f is the resonance intensity of the D1 line of potassium atoms, n is the number density of potassium atoms, l is the length of the interaction between light and atoms, r e is the electron radius, Γ is the full width at half maximum of the Lorentzian line broadening, v is the actual frequency of the light beam, v0 is the central frequency of potassium atoms in the atomic cell, is the first harmonic component of the electron spin in the z direction, and θ is the angle between the fast axis of the quarter-wave plate A9 and the polarization direction of the transmitted light (e light) of the Glan-Taylor prism A8.

[0050] The content not described in detail in the specification of the present invention belongs to the prior art well-known to those skilled in the art. It is hereby pointed out that the above description helps those skilled in the art to understand the present invention, but does not limit the protection scope of the present invention. Any implementation that makes equivalent substitutions, modifications and improvements, and / or simplifies the above description without departing from the essential content of the present invention falls within the protection scope of the present invention.

Claims

1. A reflective single-beam dual-axis atomic spin gyroscope, characterized in that It includes a first pumping beam incident on the atomic gas cell in the positive z-axis direction and a second pumping beam incident on the atomic gas cell in the negative z-axis direction. The second pumping beam is a reflected beam formed by reflecting the first pumping beam after it exits the atomic gas cell through a mirror. After the second pumping beam exits the atomic gas cell, it is reflected to the photoelectric detection balanced differential detection module through the reflection side of a non-polarizing beam splitter prism. The photoelectric detection balanced differential detection module transmits the differential signal to the phase-locked amplifier signal acquisition module, and the phase-locked amplifier signal acquisition module acquires the rotation signal and realizes the decoupling of the two-axis inertial signal by adjusting the phase shift of the reference signal.

2. The reflective single-beam two-axis atomic spin gyroscope according to claim 1, characterized in that, The first pumping beam comes from a laser, and the laser is connected to the atomic gas cell through a first half-wave plate, a first polarizing beam splitter prism, a first polarizer, a liquid crystal phase retarder, a second polarizer, a second half-wave plate, a Glan-Taylor prism, a quarter-wave plate, and the non-polarizing beam splitter prism connected in series in sequence.

3. The reflective single-beam dual-axis atomic spin gyroscope according to claim 2, wherein The reflection side of the first polarizing beam splitter prism is connected to a frequency stabilization module, the frequency stabilization module is connected to the laser, the reflection side of the Glan-Taylor prism is connected to a pumping laser light intensity stabilization circuit, and the pumping laser light intensity stabilization circuit is connected to the liquid crystal phase retarder.

4. The reflective single-beam dual-axis atomic spin gyroscope according to claim 1, characterized in that, The photoelectric detection balanced differential detection module includes a first photodetector and a second photodetector respectively connected to the phase-locked amplifier signal acquisition module. The first photodetector is connected to the transmission side of a second polarizing beam splitter prism, the second photodetector is connected to the reflection side of the second polarizing beam splitter prism, and the input side of the second polarizing beam splitter prism is connected to the reflection side of the non-polarizing beam splitter prism through a third half-wave plate.

5. The reflective single-beam two-axis atomic spin gyroscope according to claim 1, characterized in that An oven, a three-axis coil, and a magnetic shielding layer are sequentially arranged outward around the atomic gas cell.

6. The reflective single-beam two-axis atomic spin gyroscope according to claim 1, characterized in that The atomic gas cell is filled with an alkali metal, an inert gas, and a quenching gas.

7. The reflective single-beam two-axis atomic spin gyroscope according to claim 1, wherein The adjustment of the phase shift of the reference signal includes inputting a fixed angular rate in the y direction through a high-precision turntable and adjusting the phase shift φ of the demodulation reference signal. When the demodulation signal is no longer sensitive to the angular rate in the y direction, the system output channel corresponding to this phase shift is defined as the first output channel CH1, and this channel is only sensitive to the rotational input in the x direction; the demodulation phase of the other output channel is φ + 90°, and the system output channel corresponding to this phase shift is defined as the second output channel CH2, and this channel is only sensitive to the rotational input in the y direction, thus completing the decoupling of the two-axis signal.

8. The reflective single-beam two-axis atomic spin gyroscope according to claim 7, wherein The decoupling of the two-axis inertial signal includes that the phase shift φ output by the first output channel CH1 is determined by zeroing the coupling response of the rotational input in the y direction, and the specific phase shift of the second output channel CH2 is determined according to the rotational coupling response of zeroing the x direction.

9. The reflective single-beam dual-axis atomic spin gyroscope according to claim 1, characterized in that, The operation of the gyroscope includes the following steps: Step 1, install the reflective single-beam two-axis atomic spin gyroscope on the carrier platform, turn on the heating system, perform precise magnetic field compensation on the residual magnetism in the shielding system, and perform optical pumping on the atomic ensemble. For the convenience of explaining the principle, we define the z direction as the propagation direction when the pumping light first enters the atomic gas cell, define the direction in which the gyroscope points to the sky as the y direction, and the x direction can be obtained through the right-hand rule; Step 2: Apply a rotating modulation magnetic field on a plane perpendicular to the pumping light where B m is the amplitude of the rotating modulation magnetic field, ω is the angular frequency of the rotating modulation magnetic field, and are unit vectors in the x and y directions. The rotating modulation magnetic field modulates the electron spin, enabling the rotational information to be modulated to a high frequency for subsequent signal extraction; Step 3: After the pumping beam exits the gas cell for the first time, adjust the position and direction of the mirror so that the beam is reflected by the mirror and passes through the gas cell again. The length of interaction with the atoms is doubled, and the signal intensity is correspondingly increased, effectively increasing the signal-to-noise ratio. Step 4: After the system signal stabilizes, apply a z-direction compensation magnetic field using the three-axis magnetic field coil, and adjust the gyroscope to the nuclear spin self-compensation state to enable it to resist environmental low-frequency magnetic noise fluctuations. Step 5: The reflected pumping beam changes its propagation direction by the non-polarizing beam splitter prism and enters the balanced differential detection module. The first harmonic signal in the light intensity signal is demodulated by the signal acquisition module of the lock-in amplifier, and the voltage response signal generated by the rotational input is extracted. Step 6: Input a fixed angular rate in the y direction through the high-precision turntable, and adjust the phase shift φ of the demodulation reference signal. When the demodulated signal is no longer sensitive to the angular rate in the y direction, define the system output channel corresponding to this phase shift as the first output channel CH1, which is only sensitive to the rotational input in the x direction; the demodulation phase of the other output channel is φ + 90°, and define the system output channel corresponding to this phase shift as the second output channel CH2, which is only sensitive to the rotational input in the y direction, completing the decoupling of the two-axis signals. Step 7: Input different angular rates in sequence through the high-precision turntable, collect the corresponding voltage signal responses, thereby calibrating the relationship between the voltage signal and the rotational input, obtaining the rotational scale factor, completing the calibration and starting to use.

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