Atomic magnetometer, atomic magnetometer measurement system, and magnetic field measurement method

Abstract

An atomic magnetometer, an atomic magnetometer measurement system, and a magnetic field measurement method. The atomic magnetometer comprises a laser (1), a probe (2), a magnetic field generation unit (3), and a magnetic field compensation unit (4); the probe (2) is connected to the laser (1) by means of a polarization-maintaining collimation optical fiber (5), and light emitted by the laser (1) is used as pump light; the probe (2) is used for performing beam splitting on the pump light and in a gas chamber, forming two beams of light that are perpendicular to each other and do not intersect with each other, so as to respectively detect the two beams of light to obtain a first detection signal and a second detection signal; the magnetic field generation unit (3) is used for generating a magnetic field signal at the gas chamber on the basis of modulation signals in three directions; the magnetic field compensation unit (4) is used for compensating, on the basis of the modulation signals in the three directions, the first detection signal and the second detection signal, magnetic fields to be measured in the three directions to zero, and performing measurement to obtain said magnetic fields. The atomic magnetometer, the atomic magnetometer measurement system, and the magnetic field measurement method can enlarge a bandwidth range for measurement.

Description

Atomic magnetometer, atomic magnetometer measurement system and magnetic field measurement method Technical Field

[0001] The present invention relates to the technical field of measuring equipment, and in particular to an atomic magnetometer, an atomic magnetometer measurement system and a magnetic field measurement method. Background Art

[0002] The atomic magnetometer is a magnetic field strength detection device that is currently widely used in the world. It has the characteristics of large range, high sensitivity and light weight. It has important applications in geophysical research, mineral exploration, ocean exploration, archaeological excavation, large-scale construction, environmental protection and military defense.

[0003] With the advancement of laser technology, a variety of optically pumped atomic magnetometers based on the interaction between atoms and lasers have emerged. Among them, atomic magnetometers based on spin-exchange relaxation-free (SERF) have attracted widespread attention. The spin-exchange relaxation-free atomic magnetometer is currently the most sensitive optically pumped atomic magnetometer. It has the advantages of being sensitive to low-frequency signals, not requiring cryogenic cooling, low power consumption, and easy miniaturization, and has therefore been widely used. However, the probe bandwidth of the miniaturized atomic magnetometers based on spin-exchange relaxation-free on the market is currently less than 200 Hz, and the magnetic field measurement is limited by dimensionality, and the bandwidth range is also narrow. Therefore, how to propose a three-axis vector atomic magnetometer with wider bandwidth and higher sensitivity has become an important issue that needs to be urgently addressed in this field.

[0004] Summary of the Invention

[0005] In response to the problems in the prior art, embodiments of the present invention provide an atomic magnetometer, an atomic magnetometer measurement system, and a magnetic field measurement method, which can at least partially solve the problems in the prior art.

[0006] In one aspect, an atomic magnetometer includes a laser, a probe, a magnetic field generating unit, and a magnetic field compensating unit, wherein:

[0007] The probe is connected to the laser via a polarization-maintaining collimating optical fiber, and the light emitted by the laser is introduced as pump light;

[0008] The probe is used to split the pump light and form two perpendicular and non-intersecting beams of light in the gas chamber, so as to respectively detect the two beams of light to obtain a first detection signal and a second detection signal;

[0009] The magnetic field generating unit is used to generate a magnetic field signal at the gas chamber based on the modulation signals in three directions, and the magnetic field compensation unit is used to compensate the magnetic fields to be measured in three directions to zero based on the modulation signals in three directions, the first detection signal and the second detection signal, and measure and obtain the magnetic field to be measured.

[0010] Furthermore, the probe includes a polarizer, a polarization beam splitter, a circular polarizer, an air chamber, a first photodetector, a right-angle reflection prism, a half-wave plate, a polarization combination prism and a second photodetector, wherein:

[0011] The polarizer is used to stabilize the polarization direction of the incident pump light; the polarization beam splitter splits the pump light into two beams of light, the first beam of light is the transmitted light passing through the polarization beam splitter, and the second beam of light is the refracted light passing through the polarization beam splitter;

[0012] The first beam of light is incident into the air chamber through the circular polarizer, interacts with the atoms in the air chamber, and then is emitted to the first photodetector; the second beam of light is incident into the air chamber through the right-angle reflection prism, the half-wave plate, and the polarization combination prism in sequence, interacts with the atoms in the air chamber, and then is emitted to the second photodetector; the first beam of light and the second beam of light incident into the air chamber are perpendicular to each other and are at a preset distance apart.

[0013] Furthermore, the preset distance is greater than or equal to 1.6 mm and less than or equal to 2.1 mm.

[0014] Furthermore, the magnetic field generating unit includes a signal generator and a first dual-plane stream function coil, wherein:

[0015] The signal generator is connected to the first dual-plane stream function coil, and is used to generate modulation signals in three directions. The modulation signals in three directions enable the first dual-plane stream function coil to generate a magnetic field signal. The magnetic field signal includes a compensation field signal and a three-axis modulation signal. The compensation field signal is used to compensate the residual magnetic field at the air chamber to zero field, and the three-axis modulation signal is used to generate modulation magnetic fields in three directions perpendicular to each other at the air chamber.

[0016] Furthermore, the magnetic field compensation unit includes: a first current amplifier, a first lock-in amplifier, a first PI controller, a second current amplifier, a second lock-in amplifier, a second PI controller, a third PI controller and a second dual-plane stream function coil, wherein:

[0017] The first current amplifier is used to convert the first detection signal into a voltage signal and amplify the voltage signal to obtain a first amplified signal;

[0018] The first lock-in amplifier is used to perform signal demodulation based on the modulation signal in the first direction and the first amplified signal to obtain a first direction component of the demodulated signal;

[0019] The first PI controller is configured to obtain a first compensation signal based on a first direction component of the demodulated signal, and output the first compensation signal to the second dual-plane stream function coil to compensate the magnetic field to be measured in the first direction to zero;

[0020] The second current amplifier is used to convert the second detection signal into a voltage signal and amplify the voltage signal to obtain a second amplified signal;

[0021] The second lock-in amplifier is used to perform signal demodulation based on the modulated signal in the third direction and the second amplified signal to obtain a second direction component and a third direction component of the demodulated signal;

[0022] The second PI controller is configured to output a second compensation signal based on a second direction component of the demodulated signal, and output the second compensation signal to the second dual-plane stream function coil to compensate the magnetic field to be measured in the second direction to zero;

[0023] The third PI controller is configured to output a third compensation signal based on a third direction component of the demodulated signal, and output the third compensation signal to the second dual-plane stream function coil to compensate the magnetic field to be measured in the third direction to zero.

[0024] Furthermore, the air chamber is provided with a heating plate, and the heating plate is used to heat the air chamber to a target temperature.

[0025] Furthermore, the gas chamber is filled with rubidium atoms and nitrogen.

[0026] Furthermore, the atomic magnetometer provided in the embodiment of the present invention further includes a data acquisition card, and the data acquisition card is connected to the magnetic field compensation unit.

[0027] On the other hand, the present invention provides an atomic magnetometer measurement system, comprising the atomic magnetometer described in any one of the above embodiments and a host computer, wherein the atomic magnetometer is connected to the host computer.

[0028] In another aspect, the present invention provides a magnetic field measurement method based on the atomic magnetometer described in any one of the above embodiments, comprising:

[0029] The light emitted by the laser is introduced into the probe through a polarization-maintaining collimated optical fiber as pump light;

[0030] The probe splits the pump light and forms two perpendicular and non-intersecting beams of light in the gas chamber;

[0031] The probe detects the two beams of light respectively to obtain a first detection signal and a second detection signal;

[0032] The magnetic field generating unit generates a magnetic field signal at the air chamber based on the adjustment signals in three directions;

[0033] The magnetic field compensation unit compensates the magnetic fields to be measured in three directions to zero based on the modulation signals in the three directions, the first detection signal, and the second detection signal, and measures and obtains the magnetic fields to be measured.

[0034] Furthermore, the magnetic field compensation unit compensates the magnetic fields to be measured in the three directions to zero based on the modulation signals in the three directions, the first detection signal, and the second detection signal, including:

[0035] Converting the first detection signal into a voltage signal and amplifying the signal to obtain a first amplified signal, and converting the second detection signal into a voltage signal and amplifying the signal to obtain a second amplified signal;

[0036] Performing signal demodulation based on the modulated signal in the first direction and the first amplified signal to obtain a first direction component of the demodulated signal; performing signal demodulation based on the modulated signal in the third direction and the second amplified signal to obtain a second direction component and a third direction component of the demodulated signal;

[0037] A first compensation signal is obtained based on the first direction component of the demodulated signal, and the first compensation signal is output to the second dual-plane stream function coil to compensate the magnetic field to be measured in the first direction to zero; a second compensation signal is output based on the second direction component of the demodulated signal, and the second compensation signal is output to the second dual-plane stream function coil to compensate the magnetic field to be measured in the second direction to zero; a third compensation signal is output based on the third direction component of the demodulated signal, and the third compensation signal is output to the second dual-plane stream function coil to compensate the magnetic field to be measured in the third direction to zero.

[0038] Furthermore, the magnetic field signal includes a compensation signal and a three-axis modulation signal, the compensation signal is used to compensate the residual magnetic field at the gas chamber to zero field, and the three-axis modulation signal is used to generate a modulated magnetic field in three directions perpendicular to each other at the gas chamber.

[0039] Furthermore, before the light emitted by the laser is introduced into the probe as pump light through the polarization-maintaining collimating optical fiber, the following steps are also included:

[0040] The gas chamber is heated to a target temperature by a heating plate provided in the gas chamber.

[0041] An atomic magnetometer, an atomic magnetometer measurement system, and a magnetic field measurement method provided by an embodiment of the present invention include a laser, a probe, a magnetic field generating unit, and a magnetic field compensation unit. The probe is connected to the laser via a polarization-maintaining collimated optical fiber, and introduces light emitted by the laser as pump light. The probe is used to split the pump light and obtain a first detection signal and a second detection signal by detecting two perpendicular and non-intersecting beams of light in an air chamber. The magnetic field generating unit is used to generate a magnetic field signal based on modulation signals in three directions. The magnetic field compensation unit is used to compensate the magnetic fields to be measured in three directions to zero based on the modulation signals in the three directions, the first detection signal, and the second detection signal, and measure the magnetic field to be measured, thereby increasing the measurement bandwidth range. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative work. In the drawings:

[0043] FIG1 is a schematic structural diagram of an atomic magnetometer provided by a first embodiment of the present invention.

[0044] FIG2 is a schematic structural diagram of a probe provided by a second embodiment of the present invention.

[0045] FIG3 is a schematic structural diagram of an atomic magnetometer provided by a third embodiment of the present invention.

[0046] FIG4 is a schematic structural diagram of a magnetic field compensation unit provided by a fourth embodiment of the present invention.

[0047] FIG5 is a schematic structural diagram of an atomic magnetometer provided by a fifth embodiment of the present invention.

[0048] FIG6 is a schematic structural diagram of an atomic magnetometer measurement system provided by a sixth embodiment of the present invention.

[0049] FIG7 is a schematic structural diagram of an atomic magnetometer provided by a seventh embodiment of the present invention.

[0050] FIG8 is a schematic diagram of the measurement bandwidth of an atomic magnetometer provided by an eighth embodiment of the present invention.

[0051] FIG9 is a schematic diagram of the measurement sensitivity of an atomic magnetometer provided by the ninth embodiment of the present invention.

[0052] FIG10 is a flow chart of a magnetic field measurement method provided in the tenth embodiment of the present invention.

[0053] FIG11 is a flow chart of a magnetic field measurement method provided by the eleventh embodiment of the present invention.

[0054] FIG12 is a schematic diagram showing measurement results of the atomic magnetometer provided in the twelfth embodiment of the present invention.

[0055] FIG13 is a schematic diagram of measurement results of the atomic magnetometer provided in the thirteenth embodiment of the present invention.

[0056] FIG14 is a schematic diagram showing measurement results of the atomic magnetometer provided in the fourteenth embodiment of the present invention.

[0057] FIG15 is a schematic diagram showing measurement results of the atomic magnetometer provided in the fifteenth embodiment of the present invention. DETAILED DESCRIPTION

[0058] To make the purpose, technical solutions and advantages of the embodiments of the present invention more clear, the embodiments of the present invention are further described in detail below with reference to the accompanying drawings. Here, the illustrative embodiments of the present invention and their descriptions are used to explain the present invention, but are not intended to limit the present invention. It should be noted that, unless there is a conflict, the embodiments and features in the embodiments of this application can be combined with each other in any manner.

[0059] In order to facilitate understanding of the technical solution provided by this application, the relevant contents of the technical solution of this application are first explained below.

[0060] The atomic magnetometer provided in the embodiment of the present invention is a small vector atomic magnetometer with high bandwidth and high sensitivity. It can perform three-axis magnetic field measurements simultaneously, has a wider measurement bandwidth, is compatible with highly uniform magnetic field coils, is easy to adjust, and has high signal strength.

[0061] FIG1 is a schematic structural diagram of an atomic magnetometer provided by a first embodiment of the present invention. As shown in FIG1 , the atomic magnetometer provided by an embodiment of the present invention includes a laser 1, a probe 2, a magnetic field generating unit 3, and a magnetic field compensation unit 4, wherein:

[0062] The probe 2 is connected to the laser 1 through the polarization-maintaining collimating optical fiber 5, and the light emitted by the laser 1 is introduced as pump light;

[0063] The probe 2 is used to split the pump light and form two perpendicular and non-intersecting beams of light in the air chamber, so as to respectively detect the two beams of light to obtain a first detection signal and a second detection signal; the probe 2 includes an air chamber;

[0064] The magnetic field generating unit 3 is used to generate a magnetic field signal at the gas chamber based on the modulation signals in three directions, and the magnetic field compensation unit 4 is used to compensate the magnetic fields to be measured in three directions to zero based on the modulation signals in the three directions, the first detection signal and the second detection signal, and measure and obtain the magnetic field to be measured.

[0065] Specifically, the light emitted by the laser 1 passes through the polarization-maintaining collimating optical fiber 5 and is incident on the probe 2 as pump light. The probe 2 can split the pump light into two beams of light through a polarizing beam splitter (PBS). The two beams of light will enter the air chamber respectively. The two beams of light entering the air chamber are perpendicular and non-intersecting. The probe 2 can detect the two beams of light respectively through two photodetectors to obtain a first detection signal and a second detection signal.

[0066] The magnetic field generating unit 3 generates modulation signals in three directions, and the three directions are three directions perpendicular to each other. The magnetic field generating unit 3 generates a magnetic field signal at the air chamber based on the modulation signals in the three directions. The magnetic field signal includes a compensation field signal and a three-axis modulation signal. The compensation field signal is used to compensate the residual magnetic field at the air chamber to a zero field, and the three-axis modulation signal is used to generate a modulated magnetic field in three directions perpendicular to each other at the air chamber.

[0067] The magnetic field compensation unit 4 is used to perform closed-loop compensation on the magnetic fields to be measured in the three directions based on the modulation signals in the three directions, the first detection signal and the second detection signal, and compensate the magnetic fields to be measured in the three directions to zero. The magnetic field to be measured can be measured by the corresponding reverse compensation magnetic field, thereby realizing the measurement of the three-axis magnetic field.

[0068] The introduction of magnetic field compensation unit 4 increases the measurement bandwidth of the atomic magnetometer. Compared to existing miniaturized atomic magnetometers with a measurement bandwidth below 200 Hz, the atomic magnetometer provided by the embodiment of the present invention can achieve a measurement bandwidth of 1100 Hz. Furthermore, the atomic magnetometer provided by the embodiment of the present invention can maintain an average sensitivity of 35 fT / Hz1 / 2 across the frequency band.

[0069] The atomic magnetometer provided by an embodiment of the present invention includes a laser, a probe, a magnetic field generating unit, and a magnetic field compensation unit. The probe is connected to the laser via a polarization-maintaining collimated optical fiber, and the light emitted by the laser is introduced as pump light. The probe is used to split the pump light and form two perpendicular and non-intersecting beams of light in an air chamber, so as to detect the two beams of light separately to obtain a first detection signal and a second detection signal. The magnetic field generating unit is used to generate a magnetic field signal at the air chamber based on a modulation signal in three directions. The magnetic field compensation unit is used to compensate the magnetic field to be measured in three directions to zero based on the modulation signal in the three directions, the first detection signal, and the second detection signal, and measure the magnetic field to be measured, thereby increasing the measurement bandwidth range. In addition, the three-axis magnetic field measurement can be achieved simultaneously, and the measurement sensitivity can be improved.

[0070] FIG2 is a schematic structural diagram of an atomic magnetometer provided by a second embodiment of the present invention. As shown in FIG2 , on the basis of the above embodiments, the probe 2 further includes a polarizer 21, a polarization beam splitter 22, a circular polarizer 23, a gas chamber 24, a first photodetector 25, a right-angle reflection prism 26, a half-wave plate 27, a polarization combination prism 28, and a second photodetector 29, wherein:

[0071] The polarizer 21 is used to stabilize the polarization direction of the incident pump light; the polarization beam splitter 22 splits the pump light into two beams, the first beam is the transmitted light passing through the polarization beam splitter 22, and the second beam is the refracted light passing through the polarization beam splitter 22;

[0072] The first beam of light is incident into the gas chamber 24 through the circular polarizer 23, and interacts with the atoms in the gas chamber 24 before being emitted to the first photodetector 25; the second beam of light is incident into the gas chamber 24 through the right-angle reflection prism 26, the half-wave plate 27 and the polarization combination prism 17 in sequence, and interacts with the atoms in the gas chamber 24 before being emitted to the second photodetector 29; the first beam of light and the second beam of light incident into the gas chamber 24 are perpendicular to each other and are at a preset distance apart.

[0073] Specifically, all optical elements included in the probe 2 can be integrated into a 3D printed structure. The light emitted by the laser 1 is introduced by the polarization-maintaining collimating fiber 5, and the polarization direction of the incident pump light is stabilized by the polarizer 21, so that the polarization axis of the polarizer 21 is kept consistent with the polarization axis of the output light of the polarization-maintaining collimating fiber 5. The pump light passing through the polarizer 21 is incident on the polarization beam splitter 22, and the polarization beam splitter 22 divides the light into two beams. The transmitted light passing through the polarization beam splitter 22 enters the circular polarizer 23, which is used to generate circularly polarized light. The circularly polarized light emitted after passing through the circular polarizer 23 enters the air chamber 24, which is the place where the interaction between light, magnetic field and atoms occurs. After passing through the air chamber 24, the light is incident on the first photodetector 25 for detection to obtain a first detection signal. The refracted light from polarization beam splitter 22 enters right-angle reflection prism 26, where it is reflected. After passing through half-wave plate 27, it enters polarization combination prism 28 equipped with a circular polarizer. After passing through polarization combination prism 28, the light emerges as circularly polarized light. The emitted circularly polarized light enters gas cell 24, where it is incident on second photodetector 29, which detects it and generates a second detection signal. The two circularly polarized light beams entering gas cell 24 are vertically offset, perpendicular to each other, and separated by a predetermined distance.

[0074] On the basis of the above embodiments, further, the preset distance is greater than or equal to 1.6 mm and less than or equal to 2.1 mm.

[0075] FIG3 is a schematic structural diagram of an atomic magnetometer provided in a third embodiment of the present invention. As shown in FIG3 , based on the above embodiments, the magnetic field generating unit 3 further includes a signal generator 31 and a first dual-plane stream function coil 32, wherein:

[0076] The signal generator 31 is connected to the first dual-plane stream function coil 32. The signal generator 31 is used to generate modulation signals in three directions. The modulation signals in the three directions enable the first dual-plane stream function coil 32 to generate a magnetic field signal. The magnetic field signal includes a compensation field signal and a three-axis modulation signal. The compensation field signal is used to compensate the residual magnetic field at the gas chamber to zero field, and the three-axis modulation signal is used to generate a modulation magnetic field in three directions perpendicular to each other at the gas chamber.

[0077] Specifically, the three-directional modulation signals generated by the signal generator 31 can be transmitted to the first dual-plane stream function coil 32 via a shielded cable. The magnetic field signals generated by the first dual-plane stream function coil 32 are represented as: Bx0+Bxm, By0+Bym, Bz0+Bzm, where Bx0, By0, and Bz0 are compensation signals used to compensate the residual magnetic field in the air chamber 24 to zero field, and Bxm, Bym, and Bzm are three-axis modulation signals, which are sinusoidal AC signals of the same frequency. Bxm and Bzm have a fixed 90-degree phase difference relative to Bym, and are used to generate three mutually perpendicular modulated magnetic fields in the air chamber 24. The modulation frequency can be in the kHz range, for example, 3kHz, and the magnetic field amplitude can be in the hundreds of nanowatts.

[0078] FIG4 is a schematic structural diagram of a magnetic field compensation unit provided in a fourth embodiment of the present invention. As shown in FIG4 , on the basis of the above embodiments, the magnetic field compensation unit 4 further includes: a first current amplifier 41, a first lock-in amplifier 42, a first PI controller 43, a second current amplifier 44, a second lock-in amplifier 45, a second PI controller 46, a third PI controller 47, and a second dual-plane stream function coil 48, wherein:

[0079] The first current amplifier 41 is used to convert the first detection signal into a voltage signal and amplify it to obtain a first amplified signal;

[0080] The first lock-in amplifier 42 is used to perform signal demodulation based on the modulation signal in the first direction and the first amplified signal to obtain a first direction component of the demodulated signal;

[0081] The first PI controller 43 is configured to obtain a first compensation signal based on the first direction component of the demodulated signal, and output the first compensation signal to the second dual-plane stream function coil 48 to compensate the magnetic field to be measured in the first direction to zero;

[0082] The second current amplifier 44 is used to convert the second detection signal into a voltage signal and amplify it to obtain a second amplified signal;

[0083] The second lock-in amplifier 45 is used to perform signal demodulation based on the modulated signal in the third direction and the second amplified signal to obtain the second direction component and the third direction component of the demodulated signal;

[0084] The second PI controller 46 is configured to obtain a second compensation signal based on the second direction component of the demodulated signal, and output the second compensation signal to the second dual-plane stream function coil 48 to compensate the magnetic field to be measured in the second direction to zero;

[0085] The third PI controller 47 is configured to output a third compensation signal based on the third direction component of the demodulated signal, and output the third compensation signal to the second biplanar stream function coil 48 to compensate the magnetic field to be measured in the third direction to zero.

[0086] Specifically, the first detection signal is converted into a voltage signal by a first current amplifier 41 and amplified to obtain a first amplified signal. The first amplified signal is transmitted to a first phase-locked amplifier 42 for demodulation, obtaining a first direction (X direction) component of the demodulated signal. The demodulated reference signal is the first direction modulation signal generated by the magnetic field generating unit 3. The first direction component of the demodulated signal is input into a first PI controller 43. The first compensation signal output by the first PI controller 43 is connected to the second dual-plane stream function coil 48 via a shielded wire to generate a first direction compensation magnetic field Bx_fb. Setting appropriate P and I parameters of the first PI controller 43 can compensate the measured magnetic field in the first direction to zero field in real time. In this way, the measured magnetic field in the first direction is equal to the compensation magnetic field in the opposite direction, that is, the magnetic field in the first direction Bx = -Bx_fb. Bx_fb can be calculated based on the output voltage of the first PI controller and the coil constant.

[0087] The second detection signal is converted into a voltage signal by a second current amplifier 44 and amplified to produce a second amplified signal. The second amplified signal is then transmitted to a second lock-in amplifier 45 for demodulation, producing a second direction (Y direction) component and a third direction (Z direction) component of the demodulated signal. The demodulated reference signal is the modulation signal in the third direction generated by the magnetic field generating unit 3. The second direction component and the third direction component of the demodulated signal are respectively input into a second PI controller 46 and a third PI controller 47. The second compensation signal output by the second PI controller 46 is connected to the second biplane stream function coil 48 via a shielded wire to generate a second direction compensation magnetic field By_fb. By setting appropriate P and I parameters for the second PI controller 46, the measured magnetic field in the second direction can be compensated to zero field in real time. The measured magnetic field in the second direction is then equal to the reverse compensation magnetic field, i.e., the second direction magnetic field By = -By_fb. By_fb can be calculated using the output voltage of the second PI controller 46 and the coil constant. The third compensation signal output by the third PI controller 47 is connected to the second biplane stream function coil 48 via a shielded cable, generating a compensation magnetic field Bz_fb in the third direction. By appropriately setting the P and I parameters of the third PI controller 47, the measured magnetic field in the third direction can be compensated to zero field in real time. This results in the measured magnetic field in the third direction being equal to the reverse compensation magnetic field, i.e., Bz = -Bz_fb. Bz_fb can be calculated using the output voltage of the third PI controller 47 and the coil constant. These processes can be performed simultaneously, enabling real-time three-axis closed-loop compensation. This closed-loop feedback method effectively increases the magnetic field measurement bandwidth, ultimately achieving real-time, high-bandwidth, and high-sensitivity vector magnetic field measurement.

[0088] On the basis of the above embodiments, the first dual-plane stream function coil 32 and the second dual-plane stream function coil 48 are further manufactured on a circuit board by coils according to a predetermined routing method.

[0089] The design parameters of the dual-plane stream function coil include: the geometric dimensions of the coil on one side, the distance between the two planes, and the complexity of the coil. The optimization goal of the dual-plane stream function coil is that the magnetic field generated by the dual-plane stream function coil in the air chamber has high uniformity, and the leakage field generated by the dual-plane stream function coil outside the probe is as small as possible. The possible geometric dimensions of the dual-plane stream function coil and the distance range between the two planes where the dual-plane stream function coil is located are limited in combination with the geometric dimensions of the probe. The complexity of the coil needs to consider the actual processing difficulty and select a relatively low complexity. The final optimization parameters of the dual-plane stream function coil obtained by the particle swarm algorithm are used to generate the specific routing of the first dual-plane stream function coil 32 and the second dual-plane stream function coil 48. After obtaining the routing method, the first dual-plane stream function coil 32 and the second dual-plane stream function coil 48 are manufactured on the circuit board.

[0090] On the basis of the above embodiments, further, the air chamber is provided with a heating plate, and the heating plate is used to heat the air chamber to the target temperature. In order to obtain the SERF state, the air chamber needs to be heated to the target temperature, and the air chamber can be stably heated to the target temperature through the heating plate by using a high-frequency heating temperature control component. The target temperature is set according to actual needs, for example, the target temperature is 140°C, which is not limited in the embodiment of the present invention. The heating plate can adopt a non-magnetic heating plate to reduce the magnetic field interference generated by the heating plate in the air chamber. The high-frequency heating temperature control component can adopt a power amplifier and a PID regulator, and the frequency of the power amplifier is, for example, greater than 100kHz. The high-frequency heating temperature control component can perform high-frequency AC heating on the heating plate to reduce interference with the SERF state.

[0091] Based on the above embodiments, the gas chamber is further filled with rubidium atoms and nitrogen. The gas chamber may include 87Rb atoms and nitrogen. The amount of 87Rb atoms is set according to actual needs and is not limited in this embodiment of the present invention. Nitrogen can be used as a buffer gas at a concentration of several hundred Torr.

[0092] FIG5 is a schematic diagram of the structure of an atomic magnetometer provided in a fifth embodiment of the present invention. As shown in FIG5 , based on the above embodiments, the atomic magnetometer provided in this embodiment of the present invention further includes a data acquisition card 6, which is connected to the magnetic field compensation unit 4. The data acquisition card 6 can acquire the magnetic field to be measured obtained by the magnetic field compensation unit 4.

[0093] For example, the magnetic field compensation unit 4 includes a first PI controller 43, a second PI controller 46, a third PI controller 47 and a second dual-plane stream function coil; the data acquisition card 6 is connected to the first PI controller 43, the second PI controller 46 and the third PI controller 47 respectively.

[0094] FIG6 is a schematic diagram of the structure of an atomic magnetometer measurement system provided by a sixth embodiment of the present invention. As shown in FIG6 , the atomic magnetometer measurement system provided by an embodiment of the present invention includes an atomic magnetometer 601 described in any of the above embodiments and a host computer 602. Atomic magnetometer 601 is connected to host computer 602. The magnetic fields in three directions measured by atomic magnetometer 601 can be output to host computer 602.

[0095] FIG7 is a schematic structural diagram of an atomic magnetometer provided by a seventh embodiment of the present invention. As shown in FIG7 , the atomic magnetometer provided by the embodiment of the present invention includes: a laser 1, a probe 2, a magnetic field generating unit 3, and a magnetic field compensation unit 4, wherein:

[0096] The probe 2 includes a polarizer 21, a polarization beam splitter 22, a circular polarizer 23, an air chamber 24, a first photodetector 25, a right-angle reflection prism 26, a half-wave plate 27, a polarization combining prism 28 and a second photodetector 29;

[0097] The magnetic field generating unit 3 includes a signal generator 31 and a first dual-plane stream function coil 32;

[0098] The magnetic field compensation unit 4 includes a first current amplifier 41, a first phase-locked amplifier 42, a first PI controller 43, a second current amplifier 44, a second phase-locked amplifier 45, a second PI controller 46, a third PI controller 47 and a second dual-plane stream function coil 48; the first photodetector 25 is connected to the first current amplifier 41 (not shown in the figure), and the second photodetector 29 is connected to the second current amplifier 44 (not shown in the figure).

[0099] The light emitted by the laser 1 is introduced as pump light through the polarization-maintaining collimating fiber 5. The incident pump light first passes through the polarizer 21 to stabilize its polarization direction, keeping the polarization axis of the polarizer 21 consistent with the polarization axis of the output light from the polarization-maintaining collimating fiber 5. The light is then split into two beams by the polarization beam splitter 22. The intensity ratio of the two beams is determined by the polarization direction of the pump light before passing through the polarization beam splitter 22. The transmitted light through the polarization beam splitter 22 enters the circular polarizer 23. The circularly polarized light emitted after passing through the circular polarizer 23 enters the gas chamber 24, which contains an appropriate amount of 87Rb atoms and several hundred Torr of nitrogen as a buffer gas. Finally, the optical signal is converted into a current signal by the first photodetector 25. The refracted light from polarization beam splitter 22 is reflected by right-angle reflection prism 26. The reflected light then passes through half-wave plate 27 and enters polarization combination prism 28, which includes a right-angle reflection prism and a circular polarizer. The light passing through the right-angle reflection prism of polarization combination prism 28 exits the circular polarizer of polarization combination prism 28. After passing through the circular polarizer of polarization combination prism 28, the light emerges as circularly polarized light. The emitted circularly polarized light enters gas chamber 24, where it is finally converted into a current signal by a second photodetector 29. The two circularly polarized light beams entering gas chamber 24 are vertically offset, with a center spacing of 1.85 mm ± 0.25 mm, and are perpendicular to each other. To achieve the SERF state, gas chamber 24 needs to be heated to approximately 140°C. A high-frequency heating temperature control assembly can be used to stably heat gas chamber 24 to the set temperature of 140°C using a non-magnetic heating plate. The non-magnetic heating plate can be positioned on the outer wall of gas chamber 24.

[0100] The first biplane stream function coil 32 is a coil capable of generating a three-axis magnetic field. A signal generator 31 generates the modulation signals Vx, Vy, and Vz required for the X, Y, and Z directions, which are mutually perpendicular. The modulation signals Vx, Vy, and Vz are connected to the first biplane stream function coil 32 via shielded cables, generating three-directional magnetic field signals Bx0+Bxm, By0+Bym, and Bz0+Bzm. Bx0, By0, and Bz0 are compensation signals used to compensate the residual magnetic field in the air chamber 24 within the probe 2 to zero field. Bxm, Bym, and Bzm are triaxial modulation signals, sinusoidal AC signals of the same frequency. Bxm and Bzm have a fixed 90-degree phase difference relative to Bym, generating three mutually perpendicular modulated magnetic fields in the air chamber 24. The modulation frequency is approximately 3 kHz, and the magnetic field amplitude is approximately 100 nT. The modulated light intensity signal received by the first photodetector 25 is converted into a voltage signal by the first current amplifier 41 and amplified. The amplified signal is then transmitted to the first lock-in amplifier 42 for demodulation. The demodulated reference signal is the modulated signal Vx generated by the signal generator 31. The X-direction component of the demodulated signal is input into the first PI controller 43. The output of the first PI controller 43 is connected to the second biplanar stream function coil 48 via a shielded cable to generate an X-direction compensation magnetic field Bx_fb. Setting appropriate P and I parameters for the first PI controller 43 can compensate the measured X-direction magnetic field to zero field in real time. The measured X-direction magnetic field is then equal to the inverse compensation magnetic field, i.e., Bx = -Bx_fb. Bx_fb can be calculated using the output voltage of the first PI controller 43 and the coil constant.

[0101] The modulated light intensity signal received by the second photodetector 29 is converted into a voltage signal by a second current amplifier 44 and amplified. The amplified signal is then transmitted to a second lock-in amplifier 45 for demodulation. The demodulated reference signal is the modulation signal Vz generated by the signal generator 31. The Y-direction component and the Z-direction component of the demodulated signal are input to a second PI controller 46 and a third PI controller 47, respectively. The output of the second PI controller 46 is connected to a second biplane stream function coil 48 via a shielded cable to generate a Y-direction compensation magnetic field By_fb. Setting appropriate P and I parameters for the second PI controller 46 can compensate the Y-direction magnetic field to zero in real time. The Y-direction magnetic field is then equal to the reverse compensation magnetic field, i.e., By = -By_fb. By_fb can be calculated using the output voltage of the second PI controller 46 and the coil constant. The output of the third PI controller 47 is connected via a shielded wire to the second biplane stream function coil 48, which generates the Z-direction compensation magnetic field Bz_fb. By appropriately setting the P and I parameters of the third PI controller 47, the measured Z-direction magnetic field can be compensated to zero field in real time. This results in the measured Z-direction magnetic field being equal to the inverse compensation field, i.e., Bz = -Bz_fb. Bz_fb can be calculated using the output voltage of the third PI controller 47 and the coil constant. These processes can be performed simultaneously, enabling real-time three-axis closed-loop compensation. This closed-loop feedback method effectively increases the magnetic field measurement bandwidth, ultimately enabling real-time, high-bandwidth, and high-sensitivity vector magnetic field measurement.

[0102] Figure 8 is a schematic diagram of the measurement bandwidth of an atomic magnetometer provided in the eighth embodiment of the present invention. As shown in Figure 8 , the measurement bandwidth of the atomic magnetometer provided in this embodiment of the present invention can reach 1100 Hz. Figure 9 is a schematic diagram of the measurement sensitivity of an atomic magnetometer provided in the ninth embodiment of the present invention. As shown in Figure 9 , the measurement sensitivity of the atomic magnetometer provided in this embodiment of the present invention maintains an average of 35 fT / Hz1 / 2 across the frequency band.

[0103] FIG12 is a schematic diagram of the measurement results of the atomic magnetometer provided by the twelfth embodiment of the present invention, FIG13 is a schematic diagram of the measurement results of the atomic magnetometer provided by the thirteenth embodiment of the present invention, and FIG14 is a schematic diagram of the measurement results of the atomic magnetometer provided by the fourteenth embodiment of the present invention. As shown in FIG12, 13 and 14, the atomic magnetometer provided by the embodiment of the present invention measures magnetic fields of different frequencies. Since the measurement bandwidth of the atomic magnetometer provided by the embodiment of the present invention can reach 1100 Hz, it can accurately measure magnetic field signals in three directions. However, for the miniaturized atomic magnetometers currently on the market based on spin exchange relaxation, since the probe bandwidth is lower than 200 Hz, it is impossible to accurately measure the 530 Hz and 1030 Hz magnetic field signals of FIG13 and FIG14, and there will be serious distortion.

[0104] Figure 15 is a schematic diagram of measurement results from an atomic magnetometer provided in accordance with the fifteenth embodiment of the present invention. As shown in Figure 15 , the measurement results obtained by the atomic magnetometer provided in accordance with the present invention, when measuring a magnetic field signal having a square wave waveform, essentially maintain the square wave form. A square wave can be considered a superposition of signals of different frequencies. This square wave form is maintained due to the sufficiently wide measurement bandwidth of the atomic magnetometer provided in accordance with the present invention. However, with currently available miniaturized atomic magnetometers based on spin exchange relaxation, the measurement results cannot maintain the square wave form; the rising and falling edges are significantly slowed, resulting in noticeable distortion.

[0105] FIG10 is a flow chart of a magnetic field measurement method according to a tenth embodiment of the present invention. As shown in FIG10 , the magnetic field measurement method according to an embodiment of the present invention, applicable to the atomic magnetometer described in any of the above embodiments, includes:

[0106] S1001, the light emitted by the laser is introduced into the probe through the polarization-maintaining collimated optical fiber as pump light;

[0107] Specifically, the light emitted by the laser of the atomic magnetometer passes through the polarization-maintaining collimated optical fiber and is incident on the probe as pump light.

[0108] S1002, the probe splits the pump light and forms two perpendicular and non-intersecting light beams in the gas chamber;

[0109] Specifically, the probe can split the pump light into two beams through the PBS, and the two beams enter the air chamber respectively. The two beams entering the air chamber are perpendicular and non-intersecting. The centers of the two beams are separated by a preset distance.

[0110] S1003, the probe detects the two beams of light respectively to obtain a first detection signal and a second detection signal;

[0111] Specifically, the probe can respectively detect two beams of light through two photoelectric detectors to obtain a first detection signal and a second detection signal.

[0112] S1004: The magnetic field generating unit generates a magnetic field signal at the air chamber based on the adjustment signals in three directions;

[0113] Specifically, the magnetic field generating unit generates modulation signals in three directions, and the three directions are three directions perpendicular to each other. The magnetic field generating unit generates a magnetic field signal at the air chamber based on the modulation signals in the three directions. The magnetic field signal may include a compensation field signal and a three-axis modulation signal. The compensation field signal is used to compensate the residual magnetic field at the air chamber to a zero field, and the three-axis modulation signal is used to generate a modulated magnetic field in three directions perpendicular to each other at the air chamber.

[0114] S1005: The magnetic field compensation unit compensates the magnetic fields to be measured in three directions to zero based on the modulation signals in the three directions, the first detection signal, and the second detection signal, and measures and obtains the magnetic fields to be measured.

[0115] Specifically, the magnetic field compensation unit performs closed-loop compensation on the magnetic fields to be measured in the three directions based on the modulation signals in the three directions, the first detection signal and the second detection signal, and can compensate the magnetic fields to be measured in the three directions to zero. The magnetic fields to be measured can be measured by the corresponding reverse compensation magnetic fields.

[0116] In the magnetic field measurement method provided by an embodiment of the present invention, light emitted by a laser is introduced into a probe as pump light through a polarization-maintaining collimated optical fiber; the probe splits the pump light and forms two perpendicular and non-intersecting beams of light within an air chamber; the probe detects the two beams of light separately to obtain a first detection signal and a second detection signal; a magnetic field generating unit generates a magnetic field signal at the air chamber based on adjustment signals in three directions; a magnetic field compensation unit compensates the magnetic fields to be measured in the three directions to zero based on the modulation signals in the three directions, the first detection signal, and the second detection signal, and measures the magnetic fields to be measured. The introduction of the magnetic field compensation unit to compensate for the magnetic field to be measured can increase the measurement bandwidth. Furthermore, the method can simultaneously achieve three-axis magnetic field measurement and improve measurement sensitivity.

[0117] FIG11 is a flow chart of a magnetic field measurement method provided by the eleventh embodiment of the present invention. As shown in FIG11 , based on the above embodiments, further, the magnetic field compensation unit compensates the magnetic fields to be measured in the three directions to zero based on the modulation signals in the three directions, the first detection signal, and the second detection signal, including:

[0118] S1101, converting a first detection signal into a voltage signal and amplifying the signal to obtain a first amplified signal, and converting a second detection signal into a voltage signal and amplifying the signal to obtain a second amplified signal;

[0119] Specifically, the first current amplifier of the magnetic field compensation unit converts the first detection signal into a voltage signal and amplifies it to obtain a first amplified signal; the second current amplifier of the magnetic field compensation unit converts the second detection signal into a voltage signal and amplifies it to obtain a second amplified signal.

[0120] S1102: Perform signal demodulation based on the modulated signal in the first direction and the first amplified signal to obtain a first direction component of the demodulated signal; perform signal demodulation based on the modulated signal in the third direction and the second amplified signal to obtain a second direction component and a third direction component of the demodulated signal;

[0121] Specifically, the first phase-locked amplifier of the magnetic field compensation unit performs signal demodulation based on the modulation signal of the first direction and the first amplified signal to obtain the first direction component of the demodulated signal; the second phase-locked amplifier of the magnetic field compensation unit performs signal demodulation based on the modulation signal of the third direction and the second amplified signal to obtain the second direction component and the third direction component of the demodulated signal.

[0122] S1103. Obtain a first compensation signal based on the first direction component of the demodulated signal, and output the first compensation signal to the second dual-plane stream function coil to compensate the magnetic field to be measured in the first direction to zero; output a second compensation signal based on the second direction component of the demodulated signal, and output the second compensation signal to the second dual-plane stream function coil to compensate the magnetic field to be measured in the second direction to zero; output a third compensation signal based on the third direction component of the demodulated signal, and output the third compensation signal to the second dual-plane stream function coil to compensate the magnetic field to be measured in the third direction to zero.

[0123] Specifically, the first PI controller of the magnetic field compensation unit obtains a first compensation signal based on the first direction component of the demodulated signal, and outputs the first compensation signal to the second dual-plane stream function coil to compensate the measured magnetic field in the first direction to zero; the second PI controller of the magnetic field compensation unit obtains a second compensation signal based on the second direction component of the demodulated signal, and outputs the second compensation signal to the second dual-plane stream function coil to compensate the measured magnetic field in the second direction to zero; the third PI controller of the magnetic field compensation unit outputs a third compensation signal based on the third direction component of the demodulated signal, and outputs the third compensation signal to the second dual-plane stream function coil to compensate the measured magnetic field in the third direction to zero.

[0124] On the basis of the above embodiments, further, the magnetic field signal includes a compensation field signal and a three-axis modulation signal, the compensation field signal is used to compensate the residual magnetic field at the air chamber to zero field, and the three-axis modulation signal is used to generate a modulated magnetic field in three directions perpendicular to each other at the air chamber.

[0125] Based on the above embodiments, the method further includes the following steps before the light emitted by the laser is introduced into the probe as pump light through the polarization-maintaining collimating optical fiber:

[0126] The gas chamber is heated to a target temperature by a heating plate provided in the gas chamber.

[0127] Specifically, to achieve the SERF state, the gas chamber needs to be heated to a target temperature. A high-frequency heating temperature control component can be used to stably heat the gas chamber to the target temperature via a heating plate. The target temperature is set according to actual needs, for example, 140°C, which is not limited in this embodiment of the present invention.

[0128] The present invention is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device produce a device for implementing the functions specified in one or more processes in the flowchart and / or one or more boxes in the block diagram.

[0129] These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce a product including an instruction device that implements the functions specified in one or more processes in the flowchart and / or one or more boxes in the block diagram.

[0130] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, so that the instructions executed on the computer or other programmable device provide steps for implementing the functions specified in one or more processes in the flowchart and / or one or more boxes in the block diagram.

[0131] Throughout this specification, reference to terms such as "one embodiment," "a specific embodiment," "some embodiments," "for example," "example," "specific example," or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0132] The specific embodiments described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. An atomic magnetometer, characterized in that It includes a laser, a probe, a magnetic field generating unit and a magnetic field compensating unit, wherein: The probe is connected to the laser via a polarization-maintaining collimating optical fiber, and the light emitted by the laser is introduced as pump light; The probe is used to split the pump light and form two perpendicular and non-intersecting beams of light in the gas chamber, so as to respectively detect the two beams of light to obtain a first detection signal and a second detection signal; The magnetic field generating unit is used to generate a magnetic field signal at the gas chamber based on the modulation signals in three directions, and the magnetic field compensation unit is used to compensate the magnetic fields to be measured in three directions to zero based on the modulation signals in three directions, the first detection signal and the second detection signal, and measure and obtain the magnetic field to be measured.

2. The atomic magnetometer according to claim 1, wherein The probe includes a polarizer, a polarization beam splitter, a circular polarizer, an air chamber, a first photodetector, a right-angle reflection prism, a half-wave plate, a polarization combination prism, and a second photodetector, wherein: The polarizer is used to stabilize the polarization direction of the incident pump light; the polarization beam splitter splits the pump light into two beams of light, the first beam of light is the transmitted light passing through the polarization beam splitter, and the second beam of light is the refracted light passing through the polarization beam splitter; The first beam of light is incident into the air chamber through the circular polarizer, interacts with the atoms in the air chamber, and then is emitted to the first photodetector; the second beam of light is incident into the air chamber through the right-angle reflection prism, the half-wave plate, and the polarization combination prism in sequence, interacts with the atoms in the air chamber, and then is emitted to the second photodetector; the first beam of light and the second beam of light incident into the air chamber are perpendicular to each other, and the center of the first beam of light and the center of the second beam of light are at a preset distance apart.

3. The atomic magnetometer according to claim 2, characterized in that The preset distance is greater than or equal to 1.6 mm and less than or equal to 2.1 mm.

4. The atomic magnetometer according to claim 1, wherein The magnetic field generating unit includes a signal generator and a first dual-plane stream function coil, wherein: The signal generator is connected to the first dual-plane stream function coil, and is used to generate modulation signals in three directions. The modulation signals in three directions enable the first dual-plane stream function coil to generate a magnetic field signal. The magnetic field signal includes a compensation field signal and a three-axis modulation signal. The compensation field signal is used to compensate the residual magnetic field at the air chamber to zero field, and the three-axis modulation signal is used to generate a modulation magnetic field in three directions perpendicular to each other at the air chamber.

5. The atomic magnetometer according to claim 4, characterized in that The magnetic field compensation unit includes: a first current amplifier, a first lock-in amplifier, a first PI controller, a second current amplifier, a second lock-in amplifier, a second PI controller, a third PI controller and a second dual-plane stream function coil, wherein: The first current amplifier is used to convert the first detection signal into a voltage signal and amplify the voltage signal to obtain a first amplified signal; The first lock-in amplifier is used to perform signal demodulation based on the modulation signal in the first direction and the first amplified signal to obtain a first direction component of the demodulated signal; The first PI controller is configured to obtain a first compensation signal based on a first direction component of the demodulated signal, and output the first compensation signal to the second dual-plane stream function coil to compensate the magnetic field to be measured in the first direction to zero; The second current amplifier is used to convert the second detection signal into a voltage signal and amplify the voltage signal to obtain a second amplified signal; The second lock-in amplifier is used to perform signal demodulation based on the modulated signal in the third direction and the second amplified signal to obtain a second direction component and a third direction component of the demodulated signal; The second PI controller is configured to output a second compensation signal based on a second direction component of the demodulated signal, and output the second compensation signal to the second dual-plane stream function coil to compensate the magnetic field to be measured in the second direction to zero; The third PI controller is configured to output a third compensation signal based on a third direction component of the demodulated signal, and output the third compensation signal to the second dual-plane stream function coil to compensate the magnetic field to be measured in the third direction to zero.

6. The atomic magnetometer according to claim 5, characterized in that The first dual-plane stream function coil and the second dual-plane stream function coil are manufactured on a circuit board by coils according to a predetermined routing method.

7. The atomic magnetometer according to claim 1, wherein: The air chamber is provided with a heating plate, and the heating plate is used to heat the air chamber to a target temperature.

8. The atomic magnetometer according to claim 1, wherein: The gas chamber is filled with rubidium atoms and nitrogen.

9. The atomic magnetometer according to claim 1, wherein: It also includes a data acquisition card, which is connected to the magnetic field compensation unit.

10. An atomic magnetometer measurement system, characterized in that: The invention comprises the atomic magnetometer according to any one of claims 1 to 9 and a host computer, wherein the atomic magnetometer is connected to the host computer.

11. A magnetic field measurement method based on the atomic magnetometer according to any one of claims 1 to 9, characterized in that: include: The light emitted by the laser is introduced into the probe through a polarization-maintaining collimated optical fiber as pump light; The probe splits the pump light and forms two perpendicular and non-intersecting beams of light in the gas chamber; The probe detects the two beams of light respectively to obtain a first detection signal and a second detection signal; The magnetic field generating unit generates a magnetic field signal at the air chamber based on the adjustment signals in three directions; The magnetic field compensation unit compensates the magnetic fields to be measured in three directions to zero based on the modulation signals in the three directions, the first detection signal, and the second detection signal, and measures and obtains the magnetic fields to be measured.

12. The method according to claim 11, characterized in that The magnetic field compensation unit compensates the magnetic fields to be measured in three directions to zero based on the modulation signals in the three directions, the first detection signal, and the second detection signal, including: Converting the first detection signal into a voltage signal and amplifying the signal to obtain a first amplified signal, and converting the second detection signal into a voltage signal and amplifying the signal to obtain a second amplified signal; Performing signal demodulation based on the modulated signal in the first direction and the first amplified signal to obtain a first direction component of the demodulated signal; performing signal demodulation based on the modulated signal in the third direction and the second amplified signal to obtain a second direction component and a third direction component of the demodulated signal; A first compensation signal is obtained based on the first direction component of the demodulated signal, and the first compensation signal is output to the second dual-plane stream function coil to compensate the magnetic field to be measured in the first direction to zero; a second compensation signal is output based on the second direction component of the demodulated signal, and the second compensation signal is output to the second dual-plane stream function coil to compensate the magnetic field to be measured in the second direction to zero; a third compensation signal is output based on the third direction component of the demodulated signal, and the third compensation signal is output to the second dual-plane stream function coil to compensate the magnetic field to be measured in the third direction to zero.

13. The method according to claim 11, characterized in that The magnetic field signal includes a compensation signal and a three-axis modulation signal. The compensation signal is used to compensate the residual magnetic field at the air chamber to zero field. The three-axis modulation signal is used to generate a modulation magnetic field in three mutually perpendicular directions at the air chamber.

14. The method according to any one of claims 11 to 13, characterized in that Before the light emitted by the laser is introduced into the probe as pump light through the polarization-maintaining collimated fiber, the following steps are also included: The gas chamber is heated to a target temperature by a heating plate provided in the gas chamber.

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