Enhanced diffusion pumping suppression optical frequency shift virtual magnetic field SERF atom magnetometer

Abstract

According to the enhanced diffusion pumping virtual magnetic field SERF atom magnetometer, only one laser and a light splitting element are combined, atoms in a gas chamber can be polarized through the diffusion effect, detection light is used for detection, pumping light does not directly act on the atoms detected by the detection light, and the detection efficiency is improved. The magnetometer is characterized in that the magnetometer comprises first pumping light and second pumping light which enter an air chamber in the z-axis direction, the first pumping light and the second pumping light are distributed in the y-axis direction in a spaced mode, and the first pumping light and the second pumping light are distributed in the y-axis direction in a spaced mode. Detection light entering the gas chamber in the x-axis direction is arranged in the interval, and the first pumping light, the second pumping light and the detection light all come from the same laser.

Description

Technical Field

[0001] The present invention relates to the technical field of SERF atomic magnetometers, and in particular to an enhanced diffusion pumping optical frequency shift suppression virtual magnetic field SERF atomic magnetometer. By using only one laser and a spectroscopic element combination, the diffusion effect can be used to perform pumping light pumping and detection light detection on atoms in a gas chamber, and the pumping light does not directly act on the part of atoms detected by the detection light, thereby suppressing the influence of the optical frequency shift virtual magnetic field of the pumping light on the magnetic field measurement, and improving the sensitivity of the magnetometer. Background Art

[0002] Existing optical frequency shift suppression schemes include adjusting the gas composition in the gas chamber, adjusting laser parameters, measuring the optical frequency shift virtual magnetic field and suppressing it by magnetic compensation, etc., while suppressing the optical frequency shift virtual magnetic field by diffusion effect can theoretically achieve complete suppression. The present invention uses diffusion pumping to suppress the optical frequency shift virtual magnetic field. In order to enhance the polarization efficiency, two circularly polarized pumping lights with the same polarization state and the same optical power are used for parallel pumping. The detection light passes vertically through the middle of the two pumping lights. The atoms between the two pumping lights are polarized due to the diffusion effect. Since the part of the atoms detected by the detection light is not directly affected by the pumping light, the influence of the optical frequency shift of the pumping light can be suppressed.

[0003] After searching, the relevant prior art is listed as follows:

[0004] CN115560749A discloses a system for suppressing lateral light frequency shift of an inertial measurement device without spin exchange relaxation. The system takes the inertial measurement device without spin exchange relaxation as the research object, and aims at the problem of lateral light frequency shift caused by the detuning of the detection laser. The system uses two detection lasers, blue detuning and red detuning, to detect the lateral light frequency shift caused by the blue detuning detection laser and the lateral light frequency shift caused by the red detuning, so that the lateral light frequency shift caused by the blue detuning detection laser and the lateral light frequency shift caused by the red detuning can be offset each other.

[0005] CN115219966A discloses a system and method for suppressing virtual magnetic field of optical frequency shift of optical pump magnetometer. The system takes the average value of magnetic field detection results of left-handed circularly polarized light and right-handed circularly polarized light to obtain the true value of magnetic field modulus to be measured, realizes measurement of the true value of magnetic field modulus by magnetometer, effectively suppresses virtual magnetic field of optical frequency shift caused by AC Stark effect, and improves the accuracy of magnetic detection of magnetometer.

[0006] CN114485638A A method for decoupling and suppressing the transverse light frequency shift of an atomic spin inertial measurement device. Aiming at the problem of coupling between the transverse light frequency shift caused by the circular polarization component of the laser and the transverse light frequency shift caused by the circular dichroism of the atomic ensemble, the transverse light frequency shift is decoupled by changing the circular polarization degree of the detection laser of the device to obtain the transverse light frequency shift caused only by the circular dichroism of the atomic ensemble, and the magnitude of the transverse light frequency shift caused by the circular polarization component of the detection laser is adjusted by adjusting the circular polarization degree of the detection light, so that the transverse light frequency shift caused by the circular polarization component of the detection laser and the transverse light frequency shift caused by the circular dichroism of the atomic ensemble cancel each other out.

[0007] CN113280801A is based on a method for suppressing optical frequency shift of a hybrid pumped SERF spin inertial measurement system. The total optical frequency shift of the hybrid pumped SERF atomic spin inertial measurement system is suppressed by changing the operating temperature of the alkali metal gas chamber to change the alkali metal atom density ratio, so that the total optical frequency shift of the system tends to zero.

[0008] CN112684386A discloses a closed-loop suppression method for mixed light frequency shift based on atomic collision. A quantitative gas is filled into the KRb mixed atomic gas chamber in the SERF inertial measurement device, and the quantitative gas is used to change the working center frequency, so that the position where the KRb mixed light frequency shift is zero is adjusted to the D1 line frequency of K, and a saturated absorption frequency stabilization system is used to achieve frequency stabilization, thereby suppressing the light frequency shift.

[0009] CN106226713A discloses a method for suppressing optical frequency shift of a SERF atomic magnetometer. The method uses a three-dimensional in-situ magnetic compensation technology to measure the magnitude of the magnetic field felt by atoms corresponding to different pumping light frequencies under two different pumping light intensities. After theoretical fitting and solving the measured data, the zero point of the optical frequency shift can be accurately found, thereby achieving full suppression of the optical frequency shift.

[0010] CN110426652A discloses a SERF magnetometer optical frequency shift virtual magnetic field suppression experimental device and method, which measures the center frequency of the optical frequency shift by adjusting or repeatedly setting the pumping light frequency, and then tunes the pumping light to the center frequency to eliminate the optical frequency shift and the magnetic field generated by it.

[0011] Compared with SQUID magnetometers, atomic magnetometers have the advantage of small size (SQUID, superconducting quantum interference device). Among them, SERF atomic magnetometers (SERF, Spin-Exchange Relaxation-Free, spin-exchange relaxation-free) have very high theoretical sensitivity because they suppress spin exchange relaxation while achieving very high atomic density. SERF atomic magnetometers use circularly polarized light to polarize the electrons of alkali metal atoms in the gas chamber. When the circularly polarized light is not at the resonant frequency, it will cause vector light displacement, and the atoms will feel a virtual magnetic field along the direction of the pumping light. The existence of light displacement will bring a certain magnetic field gradient to the gas chamber. This is because the circularly polarized pump light will attenuate when propagating in the gas chamber, resulting in different virtual magnetic fields at different positions, which cannot be fully compensated by shimming coils; on the other hand, when the optical power, optical frequency, and polarization state of the circularly polarized pump light fluctuate, these fluctuations will cause fluctuations in the optical frequency shift and the virtual magnetic field, which will become magnetic field noise and affect the sensitivity of the magnetometer. Due to the large pressure broadening in the SERF atomic magnetometer gas chamber, it is difficult to tune the circularly polarized pump light to the resonance point. Moreover, as the magnetometer continues to run for a period of time, the laser generated by the laser will also have a frequency drift compared to when it is turned on. At the same time, due to the pressure frequency shift in the gas chamber, it is also impossible to use the conventional saturation absorption frequency stabilization method to lock the laser frequency at the resonance point after the pressure frequency shift. The above reasons make it difficult to avoid the optical frequency shift by adjusting the laser. Summary of the invention

[0012] In view of the defects or shortcomings in the prior art, the present invention provides an enhanced diffusion pumping suppressed optical frequency shift virtual magnetic field SERF atomic magnetometer. By using only one laser and a spectroscopic element combination, the diffusion effect can be used to polarize the atoms in the gas chamber and the detection light can be used for detection. The pumping light does not directly act on the part of the atoms detected by the detection light, thereby suppressing the influence of the optical frequency shift virtual magnetic field of the pumping light on the magnetic field measurement and improving the sensitivity of the magnetometer.

[0013] The technical solution of the present invention is as follows:

[0014] An enhanced diffusion pumping suppressed optical frequency shift virtual magnetic field SERF atomic magnetometer, characterized in that it includes a first pumping light and a second pumping light both incident on a gas chamber along the z-axis direction, the first pumping light and the second pumping light are spaced apart along the y-axis direction, a detection light incident on the gas chamber along the x-axis direction is arranged in the interval, and the first pumping light, the second pumping light and the detection light all come from the same laser.

[0015] A first polarization beam splitter prism is provided on the pumping light incident side of the air chamber. After the light passes through the transmission side of the first polarization beam splitter prism, it passes through the first quarter wave plate to reach the air chamber; after the light passes through the reflection side of the first polarization beam splitter prism, it passes through the reflector and the second quarter wave plate in sequence to reach the air chamber; the light generated by the laser passes through the first polarization-maintaining optical fiber, the first collimator, and the first half wave plate in sequence to reach the input side of the first polarization beam splitter prism.

[0016] The light generated by the laser passes through the second polarization-maintaining optical fiber, the second collimator, and the linear polarizer in sequence to reach the detection light incident side of the air chamber; the detection light exit side of the air chamber passes through the second half-wave plate, the second polarization beam splitter prism, the differential photodetector, and the transimpedance amplifier in sequence, and is finally connected to the signal acquisition system.

[0017] The air chamber is located in a magnetic shielding barrel equipped with a coil, an outer peripheral surface of the air chamber is provided with an electric heating film, the electric heating film is connected to a temperature control system, and the coil is connected to a current source.

[0018] The first pumping light and the second pumping light are two circularly polarized pumping lights with the same polarization state and the same optical power.

[0019] The expression for the diffusion pumping within the space in the gas chamber is as follows:

[0020]

[0021] Where S is the atomic spin polarization, t is the time, D0 is the diffusion constant, T0 is the temperature corresponding to the diffusion constant D0, P0 is the pressure corresponding to the diffusion constant D0, T is the current working temperature, P is the buffer gas pressure, is the Laplace operator.

[0022] The features and advantages of the present invention are as follows:

[0023] 1. The present invention pumps atoms through the diffusion effect, and the pumping light does not directly act on the part of atoms detected by the detection light. In theory, the influence of the virtual magnetic field of the pumping light frequency shift on the magnetic field measurement can be completely suppressed.

[0024] 2. The present invention uses a splitting method, using two circularly polarized pumping lights with the same polarization state and the same optical power for parallel pumping to enhance the pumping efficiency.

[0025] 3. The present invention uses only one laser, which reduces the number of light sources used compared to the traditional dual-beam SERF atomic magnetometer using two lasers. The laser light source in the present invention is detuned, and the detuned pumping light can ensure that the atomic polarization in the gas chamber is more uniform, which is beneficial to the performance improvement of the magnetometer. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a schematic structural diagram of an enhanced diffusion pumping optical frequency shift suppression virtual magnetic field SERF atomic magnetometer implemented in the present invention.

[0027] Figure 2 yes Figure 1 Schematic diagram of the positions of pumping light and detection light.

[0028] The reference numerals in the accompanying drawings are as follows: 1-laser; 2-first polarization-maintaining fiber; 3-first collimator; 4-second polarization-maintaining fiber; 5-second collimator; 6-first half-wave plate; 7-first polarization splitter prism; 8-reflector; 9-first quarter-wave plate; 10-second quarter-wave plate; 11-air chamber; 12-electric heating film; 13-linear polarizer; 14-second half-wave plate; 15-second polarization splitter prism; 16-balanced differential detector; 17-magnetic shielding barrel; 18-coil; 19-transimpedance amplifier; 20-signal acquisition system; 21-temperature control system; 22-current source. DETAILED DESCRIPTION

[0029] Below is the attached figure ( Figure 1-Figure 2 ) and Examples illustrate the present invention.

[0030] Figure 1 It is a schematic structural diagram of an enhanced diffusion pumping optical frequency shift suppression virtual magnetic field SERF atomic magnetometer implemented in the present invention. Figure 2 yes Figure 1 Schematic diagram of the pumping light and detection light positions in the figure. Figure 1 to Figure 2 As shown, an enhanced diffusion pumping suppressed optical frequency shift virtual magnetic field SERF atomic magnetometer includes a first pumping light (eg, Figure 1 or Figure 2 The pump light laterally below the middle pump light) and the second pump light (e.g. Figure 1 or Figure 2 The first pumping light and the second pumping light are spaced apart along the y-axis direction, and a detection light (for example, Figure 1 or Figure 2 The first pumping light, the second pumping light and the detection light all come from the same laser 1.

[0031] The pumping light incident side of the air chamber 11 is provided with a first polarization beam splitter prism 7. After passing through the transmission side of the first polarization beam splitter prism 7, the light passes through the first quarter wave plate 9 to reach the air chamber 11; after passing through the reflection side of the first polarization beam splitter prism 7, the light passes through the reflector 8 and the second quarter wave plate 10 in sequence to reach the air chamber 11; the light generated by the laser 1 passes through the first polarization-maintaining fiber 2, the first collimator 3, and the first half wave plate 6 in sequence to reach the input side of the first polarization beam splitter prism 7. The light generated by the laser 1 passes through the second polarization-maintaining fiber 4, the second collimator 5, and the linear polarizer 13 in sequence to reach the detection light incident side of the air chamber 11; the detection light exit side of the air chamber 11 passes through the second half wave plate 14, the second polarization beam splitter prism 15, the balanced differential detector 16 and the transimpedance amplifier 19 in sequence, and is finally connected to the signal acquisition system 20.

[0032] The air chamber 11 is located in a magnetic shielding barrel 17 equipped with a coil 18. The outer peripheral surface of the air chamber 11 is provided with an electric heating film 12, the electric heating film 12 is connected to a temperature control system 21, and the coil 18 is connected to a current source 22. The first pumping light and the second pumping light are two circularly polarized pumping lights with the same polarization state and the same optical power.

[0033] The diffusion pumping expression in the interval in the gas chamber 11 is as follows:

[0034]

[0035] Where S is the atomic spin polarization, t is the time, D0 is the diffusion constant, T0 is the temperature corresponding to the diffusion constant D0, P0 is the pressure corresponding to the diffusion constant D0, T is the current working temperature, P is the buffer gas pressure, is the Laplace operator.

[0036] In order to solve the adverse effects of the virtual magnetic field of optical frequency shift on the atomic magnetometer, the present invention uses diffusion pumping to polarize alkali metal atoms to avoid direct action between the pumping light and the part of the atoms detected by the detection light, so as to suppress the virtual magnetic field of optical frequency shift. In order to enhance the polarization effect on the alkali metal atoms, a beam splitting method is used to generate two beams of parallel light with the same optical power and the same polarization state to enter the atomic gas chamber. The detection light passes vertically from the position between the two pumping lights and does not directly intersect with the pumping light. The alkali metal atoms between the two pumping lights are polarized due to the influence of diffusion, and finally the virtual magnetic field of optical frequency shift is suppressed. A laser is used as a light source to simplify the structure of the magnetometer. The laser generates both pumping laser and detection laser. The detuned pumping laser can also make the longitudinal polarization inside the atomic gas chamber more uniform.

[0037] The detuned light generated by the laser is split inside the laser and exported through two polarization-maintaining optical fibers connected by two optical fiber coupling heads. One is used as pumping light and the other is used as detection light. After the pumping light is emitted by the first collimator, it is split by the combination of the first half-wave plate and the first polarization beam splitter prism. The light in the transmission direction is converted into circularly polarized light after passing through the first quarter-wave plate. The light in the reflection direction is then reflected by the reflector and converted into circularly polarized light with the same rotation direction as the circularly polarized light in the transmission direction by the second quarter-wave plate. The polarization states of the two pumping lights are kept the same by adjusting the first quarter-wave plate and the second quarter-wave plate. The first half-wave plate is used to adjust the power of the circularly polarized light in the transmission direction and the circularly polarized light in the reflection direction to be the same. The reflector is used to adjust the direction of the light so that the two pumping lights are parallel, and the two circularly polarized lights with the same polarization state enter the gas chamber in parallel. After the detection light is emitted from the second collimator, it passes through the linear polarizer and enters the gas chamber. The incident direction is perpendicular to the direction of the pumping light, passes through the middle of the two pumping lights, and does not intersect with the two pumping lights. After passing through the gas chamber, it passes through the second half-wave plate and the second polarization beam splitter prism to convert the light rotation angle signal into the difference between the light power signals in the transmission direction and the reflection direction of the second polarization beam splitter prism, and is detected using a balanced differential detector. The second half-wave plate is used to reset the signal of the balanced differential detector to zero before the magnetometer works. The balanced differential detector converts the difference in light power into a photocurrent signal, which is converted into a voltage signal through a transimpedance amplifier, and finally collected through a signal acquisition system to obtain the magnetic field information to be measured.

[0038] The detection light passes vertically between the two pumping lights. The atoms between the two pumping lights are polarized due to the diffusion effect. Since the atoms detected by the detection light are not directly affected by the pumping light, the influence of the pumping light frequency shift can be suppressed. Using only one laser as the light source can simplify the magnetometer structure and reduce costs. Moreover, since the light source is detuned, the detuned pumping light can ensure that the polarization of atoms in the gas chamber is more uniform, which is beneficial to the performance improvement of the magnetometer.

[0039] The purpose of parallel pumping with two circularly polarized lights of the same polarization state and the same optical power is to improve the polarization efficiency.

[0040] In the SERF atomic magnetometer, when the circularly polarized pump light is not at the resonant frequency, it will cause vector light displacement. At this time, the atoms will feel a virtual magnetic field along the direction of the pump light. The virtual magnetic field B LS The expression of is,

[0041]

[0042] Among them, r e is the classical electron radius, c is the speed of light, f D1 is the oscillator strength, Ф pumpis the pumping light power, tr is the gas cell glass transmittance, γ e is the electron gyromagnetic ratio, h is Planck's constant, A pump is the pumping light spot area, v is the laser frequency, v D1 is the D1 line frequency of alkali metal atoms, Г D1 is the pressure broadening of alkali metal atoms, and s is the photon spin component. The existence of optical displacement will bring a certain magnetic field gradient to the gas chamber. This is because the circularly polarized pump light will attenuate when propagating in the gas chamber, resulting in different virtual magnetic fields at different positions, which cannot be fully compensated by the shim coil; on the other hand, when the optical power, optical frequency, and polarization state of the circularly polarized pump light fluctuate, these fluctuations will cause fluctuations in the optical frequency shift and the virtual magnetic field, which will become magnetic field noise and affect the sensitivity of the magnetometer.

[0043] The present invention uses diffusion pumping to suppress the influence of the optical frequency shift of the pumping light on the atomic magnetometer. The part of the atoms detected by the detection light is not directly affected by the pumping light, and the detection light and the pumping light do not intersect, which suppresses the vector optical frequency shift caused by the pumping light. Moreover, in order to enhance the diffusion pumping effect, the pumping light is divided into two parallel beams by using the method of spectrometry. The detection light passes vertically between the two pumping light beams. The atoms between the two pumping light beams are polarized due to the diffusion effect. Since the part of the atoms detected by the detection light is not directly affected by the pumping light, the influence of the optical frequency shift of the pumping light on the atoms can be suppressed, thereby suppressing the problem of the virtual magnetic field of the optical frequency shift on the magnetometer. The principle of diffusion pumping is:

[0044]

[0045] Among them, S is the atomic spin polarization, D0 is the diffusion constant under T0 temperature and P0 pressure, and the diffusion constant of alkali metal atoms in different buffer gases is different, T is the current working temperature, P is the buffer gas pressure, It is the Laplace operator. In the atomic gas cell, the alkali metal atoms will be polarized by the pumping light, and the diffusion effect will redistribute the spatial distribution of the atomic polarization in the gas cell, which is reflected in the diffusion of atomic polarization from the part with high polarization rate, that is, the part directly affected by the pumping light, to other parts, so that the atoms outside the coverage of the pumping light beam can also be polarized.

[0046] like Figure 1As shown, the structure of the enhanced diffusion pumped SERF atomic magnetometer is that the laser 1 generates detuned light, which is split internally and is respectively connected to the first polarization-maintaining fiber 2 and the second polarization-maintaining fiber 4 through two fiber coupling heads. One is used as pumping light and the other is used as detection light. After the pumping light is emitted by the first collimator 3, it is split by the combination of the first half-wave plate 6 and the first polarization splitting prism 7. The first half-wave plate 6 can adjust the splitting ratio. The purpose of adjusting the splitting ratio is to ensure that the circularly polarized light in the transmission direction and the circularly polarized light in the reflection direction have the same optical power. The light in the transmission direction is converted into circularly polarized light after passing through the first quarter-wave plate 9. The light in the reflection direction is then reflected by the reflector 8 and converted into circularly polarized light with the same rotation direction as the circularly polarized light in the transmission direction by the second quarter-wave plate 10. The reflector 8 is used to adjust the direction of the light to ensure that the directions of the two pumping lights are parallel. The first quarter-wave plate 9 and the second quarter-wave plate 10 are used to adjust the polarization state of the two pumping lights to ensure that the polarization states of the two pumping lights are consistent. Two beams of circularly polarized light with the same polarization state are incident on the gas chamber 11 in parallel, and the atoms between the two beams of pump light are polarized due to the influence of diffusion. Compared with the configuration of one beam of pump light, the two beams of pump light are incident in parallel, which can enhance the diffusion effect.

[0047] After the detection light is emitted through the second collimator 5, it passes through the linear polarizer 13 and enters the gas chamber 11. The incident direction is perpendicular to the direction of the pumping light and passes through the middle of the two pumping light beams. Since the atoms detected by the detection light are not directly affected by the pumping light, the influence of the pumping light frequency shift can be suppressed. After passing through the gas chamber 11, the light rotation angle signal is converted into the difference between the optical power signals in the transmission direction and the reflection direction of the second polarization beam splitter prism 15 through the second half-wave plate 14 and the second polarization beam splitter prism 15, and detected by a balanced differential detector 16. The second half-wave plate 14 is used to reset the signal of the balanced differential detector 16 to zero before the magnetometer works. The balanced differential detector 16 converts the difference in optical power into a photocurrent signal, which is converted into a voltage signal through a transimpedance amplifier 19 and collected through a signal acquisition system 20 to finally obtain the magnetic field information to be measured.

[0048] The temperature control system 21 is used to control the heating power of the electric heating film 12, and then control the temperature of the air chamber 11. The magnetic shielding barrel 17 is used to shield the external geomagnetic field. The current source 22 drives the coil 18 to compensate for the residual magnetic field to ensure that the magnetometer works in the SERF state.

[0049] The detection light passes vertically between the two pumping lights, as shown in the schematic diagram. Figure 2As shown in the figure, the atoms between the two pumping lights are polarized due to the diffusion effect. Since the atoms detected by the detection light are not directly affected by the pumping light, the effect of the pumping light frequency shift can be suppressed. Using only one laser as the light source can simplify the magnetometer structure and reduce costs. Moreover, since the light source is detuned, the detuned pumping light can ensure that the polarization of atoms in the gas chamber is more uniform, which is beneficial to the performance improvement of the magnetometer. Using two circularly polarized lights with the same polarization state and the same optical power for parallel pumping is to improve the polarization efficiency.

[0050] The contents not described in detail in the specification of the present invention belong to the prior art known to the professional and technical personnel in the field. It is pointed out here that the above description helps those skilled in the art to understand the invention, but does not limit the protection scope of the invention. Any equivalent replacement, modification and / or simplification of the above description without departing from the essence of the invention falls within the protection scope of the invention.

Claims

1. An enhanced diffusion pumping suppressed optical frequency shift virtual magnetic field SERF atomic magnetometer, characterized in that: The invention comprises a first pumping light and a second pumping light both incident on the gas chamber along the z-axis direction, the first pumping light and the second pumping light are distributed at intervals along the y-axis direction, a detection light incident on the gas chamber along the x-axis direction is arranged in the interval, and the first pumping light, the second pumping light and the detection light are all from the same laser.

2. The enhanced diffusion pumping suppressed optical frequency shift virtual magnetic field SERF atomic magnetometer according to claim 1, characterized in that: A first polarization beam splitter prism is provided on the pumping light incident side of the air chamber. After the light passes through the transmission side of the first polarization beam splitter prism, it passes through the first quarter wave plate to reach the air chamber; after the light passes through the reflection side of the first polarization beam splitter prism, it passes through the reflector and the second quarter wave plate in sequence to reach the air chamber; the light generated by the laser passes through the first polarization-maintaining optical fiber, the first collimator, and the first half wave plate in sequence to reach the input side of the first polarization beam splitter prism.

3. The enhanced diffusion pumping suppressed optical frequency shift virtual magnetic field SERF atomic magnetometer according to claim 1, characterized in that: The light generated by the laser passes through the second polarization-maintaining optical fiber, the second collimator, and the linear polarizer in sequence to reach the detection light incident side of the air chamber; the detection light exit side of the air chamber passes through the second half-wave plate, the second polarization beam splitter prism, the differential photodetector, and the transimpedance amplifier in sequence, and is finally connected to the signal acquisition system.

4. The enhanced diffusion pumping suppressed optical frequency shift virtual magnetic field SERF atomic magnetometer according to claim 1, characterized in that: The air chamber is located in a magnetic shielding barrel equipped with a coil, an outer peripheral surface of the air chamber is provided with an electric heating film, the electric heating film is connected to a temperature control system, and the coil is connected to a current source.

5. The enhanced diffusion pumping suppressed optical frequency shift virtual magnetic field SERF atomic magnetometer according to claim 1, characterized in that: The first pumping light and the second pumping light are two circularly polarized pumping lights with the same polarization state and the same optical power.

6. The enhanced diffusion pumping suppressed optical frequency shift virtual magnetic field SERF atomic magnetometer according to claim 1, characterized in that: The expression for the diffusion pumping within the space in the gas chamber is as follows: Where S is the atomic spin polarization, t is the time, D0 is the diffusion constant, T0 is the temperature corresponding to the diffusion constant D0, P0 is the pressure corresponding to the diffusion constant D0, T is the current working temperature, and P is the buffer gas pressure. is the Laplace operator.

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