Method for realizing cesium atom magnetometer system based on double closed-loop feedback control

Abstract

The invention provides an implementation method of a cesium atom magnetometer system based on double-closed-loop feedback control. The implementation method can be applied to the technical field of atom magnetic sensors and the technical field of optical pump magnetometers. The method comprises the following steps: controlling voltages at two ends of a first resistance voltage-dividing network by using a first thermistor based on an ambient temperature; controlling the output frequency of the voltage-controlled oscillator by using the first resistance voltage-dividing network based on the voltage at the two ends of the first resistance voltage-dividing network; a second thermistor is used for controlling voltages at two ends of the second resistance voltage-dividing network based on the environment temperature; controlling the output power of the radio frequency power amplifier by using a second resistance voltage-dividing network based on the voltage at the two ends of the second resistance voltage-dividing network; a voltage-controlled oscillator is utilized to output a signal with a preset frequency to a radio frequency power amplifier, the radio frequency power amplifier is utilized to inject output energy with the preset frequency and power into a cesium bulb of the cesium atom lamp so as to lighten the cesium bulb, and stable output of the radio frequency power amplifier is achieved through temperature compensation of the frequency and the power output by the radio frequency power amplifier.

Description

Technical Field

[0001] The invention relates to the technical fields of atomic magnetic sensors and optical pump magnetometers, and in particular to a method for realizing a cesium atomic magnetometer system based on double closed-loop feedback control. Background Art

[0002] Atomic magnetometers have the advantages of high sensitivity, high precision, and are not easily affected by the platform posture. They are currently the core sensors used in moving platform magnetic anomaly detection equipment, and cesium atomic magnetometers are the most widely used. Existing cesium atomic lamp technology is usually open-loop control, and there is a problem of stability that needs to be improved. In addition, the Q value of the absorption chamber in the cesium atomic magnetometer is low, which restricts the further improvement of the sensitivity of the cesium atomic magnetometer. In addition, since the chemical properties of the cesium element in the cesium atomic absorption chamber are very active, when the cesium atomic absorption chamber is working, it will cause the slow consumption of the cesium element, thereby affecting the service life of the cesium atomic absorption chamber, and then affecting the performance and life of the magnetometer. Summary of the invention

[0003] In view of the above problems, the present invention provides a method for implementing a cesium atomic magnetometer system based on double closed-loop feedback control, wherein the cesium atomic magnetometer system includes a cesium atomic lamp and a double closed-loop radio frequency excitation circuit, the double closed-loop radio frequency excitation circuit includes a first closed-loop channel, the first closed-loop channel includes a first thermistor, a second thermistor, a first resistor voltage divider network, a second resistor voltage divider network, a voltage controlled oscillator and a radio frequency power amplifier, and the method includes:

[0004] Using the first thermistor, based on the ambient temperature, to control the voltage across the first resistor divider network, wherein the first thermistor is connected in parallel with the first resistor divider network;

[0005] Using the first resistor voltage divider network, based on the voltage across the first resistor voltage divider network, the output frequency of the voltage controlled oscillator is controlled, wherein the output frequency of the voltage controlled oscillator increases as the resistor voltage divider decreases;

[0006] Using the second thermistor, based on the ambient temperature, to control the voltage across the second resistor divider network, wherein the second thermistor is connected in parallel with the second resistor divider network, and both the first thermistor and the second thermistor are negative temperature coefficient thermistors;

[0007] Using the second resistor voltage divider network, based on the voltage across the second resistor voltage divider network, the output power of the RF power amplifier is controlled, wherein the output power of the RF power amplifier decreases as the resistor voltage divider decreases;

[0008] The voltage-controlled oscillator is used to output a signal of a preset frequency to the RF power amplifier, and the RF power amplifier is used to inject the energy of the preset frequency and power output by the RF power amplifier into the cesium bulb of the cesium atomic lamp to light up the cesium bulb, and the stable output of the RF power amplifier is achieved by temperature compensation of the frequency and power output by the RF power amplifier.

[0009] According to the implementation method of the cesium atomic magnetometer system based on double closed-loop feedback control provided by the present invention, since both the voltage-controlled oscillator and the radio frequency power amplifier have temperature drift characteristics, when the ambient temperature rises, the output frequency of the voltage-controlled oscillator should decrease, and a first thermistor with a negative temperature coefficient is introduced to control the output frequency of the voltage-controlled oscillator to increase as the resistance voltage divider decreases. The output power of the radio frequency power amplifier should increase, and a second thermistor with a negative temperature coefficient is introduced to control the output power of the radio frequency power amplifier to decrease as the resistance voltage divider decreases, which plays a temperature compensation role for the drift of the frequency and power output of the radio frequency power amplifier with temperature, realizes the stable output of the radio frequency power amplifier, and improves the stability of the output of the radio frequency power amplifier. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] The above contents and other objects, features and advantages of the present invention will become more apparent through the following description of the embodiments of the present invention with reference to the accompanying drawings, in which:

[0011] Figure 1 An application scenario diagram showing a method for implementing a cesium atomic magnetometer system based on double closed-loop feedback control according to an embodiment of the present invention is shown;

[0012] Figure 2 A schematic diagram of a first closed-loop channel according to an embodiment of the present invention is shown;

[0013] Figure 3 A flow chart showing a method for implementing a cesium atomic magnetometer system based on double closed-loop feedback control according to an embodiment of the present invention is shown;

[0014] Figure 4 A schematic diagram of a dual closed-loop radio frequency excitation circuit according to an embodiment of the present invention is shown;

[0015] Figure 5 A schematic diagram of the structure of a probe in a cesium atomic magnetometer system according to an embodiment of the present invention is shown;

[0016] Figure 6 A schematic diagram of a cesium atomic absorption chamber according to an embodiment of the present invention is shown;

[0017] Figure 7 A schematic diagram of a signal processing circuit according to an embodiment of the present invention is shown;

[0018] Figure 8A schematic diagram of an absorption room temperature control circuit according to an embodiment of the present invention is shown;

[0019] Fig. 9 A schematic diagram of a cesium atomic magnetometer system according to an embodiment of the present invention is shown;

[0020] Fig.10 A schematic diagram showing the sensitivity test results of a cesium atomic magnetometer according to an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0021] Below, embodiments of the present invention will be described with reference to the accompanying drawings. However, it should be understood that these descriptions are exemplary only and are not intended to limit the scope of the present invention. In the following detailed description, for ease of explanation, many specific details are set forth to provide a comprehensive understanding of embodiments of the present invention. However, it is apparent that one or more embodiments may also be implemented without these specific details. In addition, in the following description, descriptions of known structures and technologies are omitted to avoid unnecessary confusion of concepts of the present invention.

[0022] The terms used herein are only for describing specific embodiments and are not intended to limit the present invention. The terms "comprise", "include", etc. used herein indicate the existence of the features, steps, operations and / or components, but do not exclude the existence or addition of one or more other features, steps, operations or components.

[0023] All terms (including technical and scientific terms) used herein have the meanings commonly understood by those skilled in the art unless otherwise defined. It should be noted that the terms used herein should be interpreted as having a meaning consistent with the context of this specification and should not be interpreted in an idealized or overly rigid manner.

[0024] When using expressions such as "at least one of A, B, and C, etc.", they should generally be interpreted according to the meaning of the expression commonly understood by those skilled in the art (for example, "a system having at least one of A, B, and C" should include but is not limited to a system having A alone, B alone, C alone, A and B, A and C, B and C, and / or A, B, C, etc.).

[0025] In the technical solution of the present invention, the user information (including but not limited to user personal information, user image information, user device information, such as location information, etc.) and data (including but not limited to data used for analysis, stored data, displayed data, etc.) involved are all information and data authorized by the user or fully authorized by all parties, and the collection, storage, use, processing, transmission, provision, disclosure and application of the relevant data comply with relevant laws, regulations and standards, take necessary confidentiality measures, do not violate public order and good morals, and provide corresponding operation entrances for users to choose to authorize or refuse.

[0026] In the scenario of using personal information for automated decision-making, the methods, devices, and systems provided by the embodiments of the present invention provide users with corresponding operation portals for users to choose to agree or reject the automated decision-making results; if the user chooses to reject, the expert decision-making process will be entered. The expression "automated decision-making" here refers to the activity of automatically analyzing and evaluating an individual's behavioral habits, interests and hobbies, or economic, health, credit status, etc. through computer programs, and making decisions. The expression "expert decision-making" here refers to the activity of making decisions by people who specialize in a certain field, have specialized experience, knowledge and skills, and have reached a certain level of professionalism.

[0027] In the process of implementing the present invention, it is found that an atomic magnetometer usually mainly includes a pump light source, an atomic absorption chamber and a photodetector, among which the pump light source and the atomic absorption chamber are the two core components of the atomic magnetometer, which fundamentally determine the sensitivity and life of the magnetometer.

[0028] The pump light source usually adopts cesium atomic lamp or semiconductor stabilized frequency laser source, but the latter cannot meet the field engineering application with a wide temperature range. Therefore, it is more common to use cesium atomic lamp as the pump light source. However, unlike the closed-loop control of laser, the existing cesium atomic lamp technology is usually open-loop control, and there is a stability problem that needs to be improved.

[0029] Existing cesium atomic magnetometers used in geomagnetic environments usually use inert gases (such as helium, neon, argon, etc.) or nitrogen as a single gas to control the spin exchange rate of cesium atoms. Affected by gas collision broadening or photon radiation traps, their Q value is low, which restricts the further improvement of the sensitivity of cesium atomic magnetometers.

[0030] The chemical properties of the alkali metal element in the atomic absorption chamber are very active. When the atomic absorption chamber is working, under the action of temperature and electric field, the cesium element in the form of saturated vapor will continuously diffuse into the glass wall of the gas chamber, causing the slow consumption of the cesium element, thereby affecting the service life of the cesium gas chamber and further affecting the performance and life of the entire sensor.

[0031] Based on the above, the existing technology has problems such as stability caused by open-loop control of the pump lamp of the cesium atomic magnetometer, too low Q value of the absorption chamber based on buffer gas, and short life of the atomic absorption chamber, which restrict the further improvement of the sensitivity of the cesium atomic magnetometer.

[0032] In addition, the pump light source used for the high-sensitivity cesium atomic magnetometer should have the characteristics of low noise, high stability, long life and no magnetic interference; the cesium atomic absorption chamber is the magnetic sensitive unit of the atomic magnetometer, and should have the characteristics of low spin exchange rate and long life. The lower the spin exchange rate of the absorption chamber, the higher its Q value, and the narrower the magnetic resonance line width of the absorption chamber, which is more conducive to improving the sensitivity of the magnetometer. To this end, an embodiment of the present invention provides a method for implementing a cesium atomic magnetometer system based on double closed-loop feedback control.

[0033] Figure 1 An application scenario diagram of a method for implementing a cesium atomic magnetometer system based on double closed-loop feedback control according to an embodiment of the present invention is shown.

[0034] like Figure 1 As shown, the application scenario 100 according to this embodiment may include a probe 110 and an electronics unit 120. The probe 110 may include a cesium atomic lamp 111, a cesium atomic absorption chamber 112, and a non-magnetic photodetector 113; the electronics unit 120 may include a signal processing circuit 121, a dual closed-loop radio frequency excitation circuit 122, a temperature control module 123, and a power management module 124.

[0035] Figure 2 A schematic diagram of a first closed-loop channel according to an embodiment of the present invention is shown.

[0036] According to an embodiment of the present invention, the dual closed-loop RF excitation circuit 122 may include: Figure 2 A first closed-loop channel 200 is shown.

[0037] like Figure 2 As shown, the first closed-loop channel 200 includes a first thermistor 211 , a second thermistor 221 , a first resistor voltage divider network 212 , a second resistor voltage divider network 222 , a voltage controlled oscillator 213 and a radio frequency power amplifier 223 .

[0038] According to an embodiment of the present invention, the first thermistor 211 is connected in parallel with the first resistor voltage divider network 212, and the first thermistor 211 is used to control the voltage across the first resistor voltage divider network 212 based on the ambient temperature, so as to control the output frequency of the voltage controlled oscillator 213 based on the voltage across the first resistor voltage divider network 212, wherein the output frequency of the voltage controlled oscillator 213 increases with the decrease of the resistor voltage divider.

[0039] According to an embodiment of the present invention, the second thermistor 221 is connected in parallel with the second resistor voltage divider network 222, and the second thermistor 221 is used to control the voltage across the second resistor voltage divider network 222 based on the ambient temperature, so as to control the output power of the RF power amplifier 223 based on the voltage across the second resistor voltage divider network 222, wherein the output power of the RF power amplifier 223 decreases as the resistor voltage divider decreases.

[0040] According to an embodiment of the present invention, the voltage-controlled oscillator 213 is used to output a signal of a preset frequency to the RF power amplifier 223, and utilize the RF power amplifier 223 to inject the energy of the preset frequency and power output by the RF power amplifier 223 into the cesium bulb of the cesium atomic lamp 111 to light the cesium bulb, and achieve stable output of the RF power amplifier by temperature compensation of the frequency and power output by the RF power amplifier.

[0041] The following will be based on Figure 1 The scene described by Figure 2~Figure 10 The implementation method of the cesium atomic magnetometer system based on double closed-loop feedback control in an embodiment of the present invention is described in detail.

[0042] Figure 3 The flowchart of the implementation method of the cesium atomic magnetometer system based on double closed-loop feedback control according to the embodiment of the present invention is shown.

[0043] According to an embodiment of the present invention, the cesium atomic magnetometer system may include a cesium atomic lamp 111 and a dual closed-loop RF excitation circuit 122, the dual closed-loop RF excitation circuit 122 includes a first closed-loop channel 200, the first closed-loop channel may include a first thermistor, a second thermistor, a first resistor voltage divider network, a second resistor voltage divider network, a voltage-controlled oscillator and a RF power amplifier, and the structure of the first closed-loop channel is as follows: Figure 2 shown.

[0044] like Figure 3 As shown, the method 300 includes operations S310 to S350.

[0045] In operation S310 , a voltage across a first resistor voltage divider network is controlled based on an ambient temperature using a first thermistor.

[0046] The first thermistor is connected in parallel with the first resistor voltage divider network.

[0047] According to an embodiment of the present invention, the first thermistor is connected in parallel with the first resistor voltage divider network, and based on the ambient temperature, the first thermistor can control the voltage across the first resistor voltage divider network.

[0048] For example, when the current ambient temperature changes and the resistance value of the first thermistor decreases, the voltage across the first resistor voltage divider network also decreases, that is, the resistor voltage of the first thermistor decreases.

[0049] In operation S320 , the output frequency of the voltage controlled oscillator is controlled based on the voltage across the first resistor divider network by using the first resistor divider network.

[0050] Among them, the output frequency of the voltage-controlled oscillator increases as the resistance voltage divider decreases.

[0051] According to an embodiment of the present invention, the first resistor voltage divider network is also used to control the output frequency of the voltage controlled oscillator. When the voltage across the first resistor voltage divider network decreases, the output frequency of the voltage controlled oscillator increases.

[0052] In operation S330 , a voltage across a second resistor divider network is controlled based on an ambient temperature using a second thermistor.

[0053] The second thermistor is connected in parallel with the second resistor voltage divider network, and both the first thermistor and the second thermistor are negative temperature coefficient thermistors.

[0054] According to an embodiment of the present invention, both the first thermistor and the second thermistor are negative temperature coefficient thermistors, that is, when the ambient temperature increases, the resistance values ​​of the first thermistor and the second thermistor decrease.

[0055] According to an embodiment of the present invention, the second thermistor is connected in parallel with the second resistor voltage divider network, and based on the ambient temperature, the second thermistor can control the voltage across the second resistor voltage divider network.

[0056] For example, when the current ambient temperature increases, the resistance of the second thermistor decreases, and the voltage across the second resistor voltage divider network also decreases, that is, the resistor voltage divider of the second thermistor decreases.

[0057] In operation S340, the output power of the radio frequency power amplifier is controlled based on the voltage across the second resistor divider network by using the second resistor divider network.

[0058] Among them, the output power of the RF power amplifier decreases as the resistance voltage decreases.

[0059] According to an embodiment of the present invention, the second resistor voltage divider network is also used to control the output power of the RF power amplifier. When the voltage across the second resistor voltage divider network decreases, the output power of the RF power amplifier decreases.

[0060] In operation S350, a voltage-controlled oscillator is used to output a signal of a preset frequency to a radio frequency power amplifier, and the radio frequency power amplifier is used to inject energy of the preset frequency and power output by the radio frequency power amplifier into the cesium bulb of the cesium atomic lamp to light the cesium bulb, and by temperature compensation of the frequency and power output by the radio frequency power amplifier, a stable output of the radio frequency power amplifier is achieved.

[0061] According to an embodiment of the present invention, the voltage-controlled oscillator outputs a signal of a preset frequency to the radio frequency power amplifier, so as to inject the energy of the preset frequency and power output by the radio frequency power amplifier into the cesium bulb of the cesium atomic lamp to light up the cesium bulb. The first closed-loop channel as a whole is equivalent to the excitation source of the cesium atomic lamp; the preset frequency and power represent the specific frequency and power that can light up the cesium bulb.

[0062] According to an embodiment of the present invention, the voltage-controlled oscillator has a temperature drift characteristic. The change of the ambient temperature will affect the output frequency of the voltage-controlled oscillator. When the ambient temperature rises, the output frequency of the voltage-controlled oscillator will decrease. Therefore, a first thermistor is introduced. When the ambient temperature rises, the voltage across the first resistor voltage divider network is controlled to decrease to control the output frequency of the voltage-controlled oscillator to increase, that is, temperature feedback. Thus, the temperature compensation effect is achieved for the drift of the output frequency of the voltage-controlled oscillator with temperature. When the ambient temperature decreases, the principle is the same.

[0063] According to the embodiment of the present invention, the RF power amplifier also has a temperature drift characteristic. The change of ambient temperature will affect the output power of the RF power amplifier. When the ambient temperature rises, the output power of the RF power amplifier will increase. Therefore, a second thermistor is introduced. When the ambient temperature rises, the voltage at both ends of the second resistor divider network is controlled to decrease to control the output power of the RF power amplifier to decrease, that is, temperature negative feedback, thereby achieving temperature compensation for the drift of the output power of the RF power amplifier with temperature. When the ambient temperature decreases, the principle is the same.

[0064] According to the embodiments of the present invention, since both the voltage-controlled oscillator and the RF power amplifier have temperature drift characteristics, when the ambient temperature rises, the output frequency of the voltage-controlled oscillator should decrease. A first thermistor with a negative temperature coefficient is introduced to control the output frequency of the voltage-controlled oscillator to increase as the resistance voltage divider decreases. The output power of the RF power amplifier should increase. A second thermistor with a negative temperature coefficient is introduced to control the output power of the RF power amplifier to decrease as the resistance voltage divider decreases. This provides temperature compensation for the frequency and power drift of the RF power amplifier output with temperature, thereby achieving stable output of the RF power amplifier and improving the stability of the RF power amplifier output.

[0065] According to an embodiment of the present invention, the dual closed-loop RF excitation circuit also includes a second closed-loop channel, which includes a cesium atomic lamp, a RF power amplifier and a photodetector. The implementation method of the above-mentioned cesium atomic magnetometer system based on dual closed-loop feedback control also includes: using a photodetector to monitor the power of light emitted by the cesium atomic lamp in real time, and feeding it back to the RF power amplifier, so as to adjust the output power of the RF power amplifier based on the power of light emitted by the cesium atomic lamp and the preset light power, so that the cesium atomic lamp can stably output light power.

[0066] Figure 4 A schematic diagram of a dual closed-loop radio frequency excitation circuit according to an embodiment of the present invention is shown.

[0067] According to an embodiment of the present invention, the dual closed-loop RF excitation circuit 122 can be as follows: Figure 4 shown.

[0068] like Figure 4 As shown, the second closed-loop channel 400 may include a radio frequency power amplifier 223 , a cesium atomic lamp 111 and a photodetector 410 .

[0069] According to an embodiment of the present invention, when the cesium bulb in the cesium atomic lamp 111 is lit through the above-mentioned first closed-loop channel 200, the photodetector 410 can monitor the power of the light emitted by the cesium atomic lamp in real time and feed it back to the RF power amplifier 223, that is, power feedback, so as to adjust the output power of the RF power amplifier 223 based on the power of the light emitted by the cesium atomic lamp and the preset optical power, so as to ensure that the cesium atomic lamp stably outputs optical power.

[0070] The preset optical power may represent the power value that the power of the light emitted by the cesium atomic lamp needs to maintain, and the preset optical power may be set as required.

[0071] For example, when the preset optical power is 5mW, the photodetector monitors that the power of the light emitted by the cesium atomic lamp is 4mW, which is then fed back to the RF power amplifier to adjust the output power of the RF power amplifier based on the difference between the preset optical power of 5mW and the power of 4mW of the light emitted by the cesium atomic lamp at this time, so that the cesium atomic lamp can stably output 5mW of optical power.

[0072] According to an embodiment of the present invention, the cesium atomic lamp 111 is excited by an electrodeless discharge method, and the cesium atomic lamp 111 includes an excitation structure and a cesium bulb. The first closed-loop channel as an excitation source injects energy of a specific frequency and power into the cesium bulb to light up the cesium bulb. The excitation structure is used to excite the cesium bulb to achieve energy injection. The standing wave ratio of the excitation structure is less than 1.5 to ensure that most of the injected energy is converted into light; the impedance of the excitation structure is generally 50 ohms, which matches the impedance of the first closed-loop channel, such as the impedance of the excitation structure is equal to the impedance of the first closed-loop channel, to ensure that the energy output by the first closed-loop channel can be injected into the cesium bulb; the resonant frequency of the excitation structure is consistent with the output frequency of the first closed-loop channel, which also ensures that the energy output by the first closed-loop channel can be injected into the cesium bulb.

[0073] Among them, cesium bulbs can be used as cesium atomic lamp loads. Cesium bulbs are made of alkali-resistant glass, and the inner cavity is filled with a small amount of high-purity alkali metal cesium elemental substance ( ) and a specific pressure of inert gas xenon. For example, the diameter of a cesium bulb can be 8mm, and the inner cavity is filled with 5Torr (pressure unit, Torr) of xenon and an appropriate amount of alkali metal cesium.

[0074] According to an embodiment of the present invention, when the ambient temperature is low, the output power of the RF power amplifier can be increased due to the second thermistor with a negative temperature coefficient, which is conducive to the cesium bulb to light up quickly and enter a stable state.

[0075] According to an embodiment of the present invention, based on the second closed-loop channel, the power of the light emitted by the cesium atomic lamp is monitored in real time and power feedback is performed so that the cesium atomic lamp can stably output the optical power. Therefore, based on the dual closed-loop RF excitation circuit, the first closed-loop channel uses temperature feedback to achieve stable output of the excitation source, and the second closed-loop channel uses power feedback to achieve stable output of the optical power of the cesium bulb, which solves the problem of stability of the cesium atomic lamp controlled by conventional open-loop control and breaks through the photon shot noise limitation of the traditional open-loop technology system.

[0076] According to an embodiment of the present invention, the cesium atomic magnetometer system also includes an optical component; the optical component includes a collimating lens, a filter and a combined circular polarizer; the implementation method of the above-mentioned cesium atomic magnetometer system based on double closed-loop feedback control also includes: using the collimating lens to collimate the light emitted by the cesium bulb and output the collimated light; using the filter to filter the collimated light and output light of the target wavelength; using the combined circular polarizer to polarize the light of the target wavelength and output circularly polarized pump light.

[0077] Figure 5 A schematic structural diagram of a probe in a cesium atomic magnetometer system according to an embodiment of the present invention is shown.

[0078] According to an embodiment of the present invention, the probe 110 can be more specifically as follows: Figure 5 shown.

[0079] like Figure 5 As shown, the probe 110 further includes optical components between the cesium atomic absorption chamber 112 and the cesium atomic lamp 111 , namely, a collimating lens 511 , a filter 512 and a combined circular polarizer 513 .

[0080] According to an embodiment of the present invention, the RF power amplifier 223 can inject the energy of the output specific frequency and power into the cesium bulb in the cesium atomic lamp 111 to light up the cesium bulb. The light emitted by the cesium bulb passes through the collimating lens 511, the filter 512 and the combined circular polarizer 513 in sequence.

[0081] According to an embodiment of the present invention, the collimating lens 511 can collimate the light emitted by the cesium bulb to obtain collimated light; the filter 512 can filter the collimated light to obtain light of a target wavelength, that is, the filter 512 is used to select light of a target wavelength and filter out stray light to improve the efficiency of the optical pump. The target wavelength can be the wavelength of the pump light required by the magnetometer, such as the target wavelength can be 894.5nm.

[0082] According to an embodiment of the present invention, the combined circular polarizer 513 is located at the rear end of the filter 512, and is used to convert light of the target wavelength into circularly polarized light, that is, to output circularly polarized pump light, wherein the combined circular polarizer 513 adopts a half left-handed and half right-handed combination design to minimize the directional error of the atomic magnetometer probe.

[0083] Among them, the focal length of the collimating lens 511 can be 25mm, and the bandwidth of the surface anti-reflection film can be 680~980nm; the diameter of the filter 512 can be 25mm, the transmission wavelength can be 894.5nm, the bandwidth can be 10nm, the passband transmittance is greater than 90%, the reflection wavelength is 200nm~1000nm, and the cut-off band transmittance is 0.1%.

[0084] According to the embodiment of the present invention, the light emitted by the cesium bulb includes not only the light of the desired target wavelength, but also other stray light, such as the light emitted by the gas filled in the cesium bulb. The transmission wavelength of the filter 512 is determined according to the target wavelength of the desired pump light, so as to transmit the light of the target wavelength and filter out the light of other wavelengths.

[0085] According to an embodiment of the present invention, the light emitted by the cesium bulb passes through a collimating lens, a filter and a combined circular polarizer in sequence, so that other stray light can be filtered out and only light of the target wavelength is retained. Half of the circularly polarized light is left-handed and half is right-handed after passing through the combined circular polarizer, so as to reduce the directional error of the magnetometer probe as much as possible.

[0086] According to an embodiment of the present invention, the cesium atomic magnetometer system also includes a cesium atomic absorption chamber; the implementation method of the above-mentioned cesium atomic magnetometer system based on double closed-loop feedback control also includes: pump light is incident on the cesium atomic absorption chamber; wherein, the cesium atomic absorption chamber is filled with cesium single substance, and the cesium atomic absorption chamber is also filled with buffer gas to reduce the spin-destructive collision between cesium atoms and the inner wall of the cesium atomic absorption chamber; the cesium atomic absorption chamber is also filled with quenching gas to avoid the spontaneously radiated photons from being reabsorbed and re-radiated with cesium atoms before exiting the cesium atomic absorption chamber; the inner wall of the cesium atomic absorption chamber is coated with an aluminum oxide film to reduce the diffusion rate of cesium atoms to the inner wall of the cesium atomic absorption chamber.

[0087] like Figure 5 As shown, the probe 110 further includes a cesium atomic absorption chamber 112 .

[0088] According to an embodiment of the present invention, after the light emitted by the cesium bulb in the cesium atomic lamp 111 passes through the collimating lens 511, the filter 512 and the combined circular polarizer 513, circularly polarized pump light can be obtained. The circularly polarized pump light is emitted into the cesium atomic absorption chamber 112. The circularly polarized pump light polarizes the cesium atoms in the cesium atomic absorption chamber 112 through the optical pumping action in the cesium atomic absorption chamber 112.

[0089] According to an embodiment of the present invention, the buffer gas includes methane and the quench gas includes nitrogen.

[0090] According to an embodiment of the present invention, the cesium atomic absorption chamber is made of blown alkali-resistant glass, and the cavity of the cesium atomic absorption chamber is filled with a small amount of high-purity alkali metal cesium single substance, and also filled with appropriate amounts of buffer gas and quenching gas.

[0091] According to an embodiment of the present invention, methane ( ) is used as a buffer gas mainly to reduce the probability of spin-destruction collision between alkali metal cesium atoms and the gas chamber. Nitrogen ( ) is used as a quenching gas mainly to prevent spontaneously radiated photons from being reabsorbed and reradiated multiple times by surrounding cesium atoms before exiting the absorption chamber (i.e., radiation trap). Under the control of dual gas parameters, the cesium atoms can reach the maximum polarizability, which can maximize the Q value of the absorption chamber.

[0092] The buffer gas may also include ethane as an example, and the photon is the photon of the circularly polarized pump light injected into the cesium atomic absorption chamber.

[0093] According to an embodiment of the present invention, the inner wall of the cesium atomic absorption chamber is coated with an aluminum oxide film of a specific thickness ( ), the introduction of the aluminum oxide layer can greatly reduce the diffusion rate of alkali metal elements to the wall of the glass gas chamber, solving the problem that the performance of the magnetometer is reduced or even fails due to the consumption of alkali metal elements in the cesium atomic absorption chamber.

[0094] Among them, the size of the cesium atomic absorption chamber can be , filled with 50 Torr of helium and 30 Torr of nitrogen.

[0095] Figure 6 A schematic diagram of a cesium atomic absorption chamber according to an embodiment of the present invention is shown.

[0096] like Figure 6 As shown, the cesium atomic absorption chamber is filled with alkali metal cesium atoms, buffer gas methane and quenching gas nitrogen ( ), the inner wall of the cesium atomic absorption chamber is coated with an aluminum oxide film. Among them, the gas molecules include buffer gas and quenching gas.

[0097] According to an embodiment of the present invention, in order to solve the problems of too low Q value and short life of gas chamber in cesium atomic absorption chamber, the present invention provides a multi-parameter control technology of spin exchange rate in cesium atomic absorption chamber, namely, through multi-parameter control technologies such as dual gas modulation of buffer gas and quenching gas, inner wall coating of aluminum oxide film, etc., the Q value of cesium atomic absorption chamber can be improved, breaking through the line width limit of cesium atomic magnetic resonance under single gas control, and solving the problem of short life of atomic magnetometer under high temperature working conditions.

[0098] According to an embodiment of the present invention, the optical component also includes a focusing lens and a non-magnetic photodetector; the implementation method of the above-mentioned cesium atomic magnetometer system based on double closed-loop feedback control also includes: using the focusing lens to focus the light output by the cesium atomic absorption chamber, outputting the focused light to be injected into the photosensitive surface of the non-magnetic photodetector; using the non-magnetic photodetector to convert the focused light into an electrical signal.

[0099] like Figure 5 As shown, the optical component may further include a focusing lens 514 and a non-magnetic photodetector 113, wherein the focusing lens 514 is located between the cesium atomic absorption chamber 112 and the non-magnetic photodetector 113, and the non-magnetic photodetector 113 is a photodiode.

[0100] According to an embodiment of the present invention, the focusing lens 514 can focus the light output by the cesium atomic absorption chamber to obtain focused light, which is then incident on the photosensitive surface of the non-magnetic photodetector 113, and the photodetector can convert the incident focused light into an electrical signal.

[0101] The focal length of the focusing lens 514 may be 25 mm, and the bandwidth of the surface anti-reflection film may be 680-980 nm.

[0102] According to an embodiment of the present invention, the non-magnetic photodetector is located at the rear end of the atomic magnetometer probe, and is used to receive the focused light and transmit the converted electrical signal to the signal processing board of the electronics unit 120 of the cesium atomic magnetometer system, so that the electronics unit processes the electrical signal to achieve high-speed tracking and measurement of the Larmor frequency of the magnetic field.

[0103] Among them, the outer diameter of the non-magnetic photodetector can be 22mm, the diameter of the photosensitive surface can be 8mm, and the responsivity at 894.5nm can be .

[0104] According to the embodiment of the present invention, since the non-magnetic photodetector adopts a completely non-magnetic process design, the problem of residual magnetic noise introduced by nickel plating during the gold immersion process existing in conventional photodetectors is solved.

[0105] According to an embodiment of the present invention, the cesium atomic magnetometer system also includes a signal processing circuit, which includes a preamplifier, an automatic gain control subcircuit, a phase shift subcircuit and a waveform shaping subcircuit; the implementation method of the above-mentioned cesium atomic magnetometer system based on dual closed-loop feedback control also includes: using a preamplifier to amplify the electrical signal and output the amplified electrical signal; using the automatic gain control subcircuit to perform amplitude stabilization processing on the amplified electrical signal and output a sinusoidal signal, wherein the frequency of the sinusoidal signal is the Larmor frequency; using the phase shift subcircuit to phase shift the sinusoidal signal, output the phase shifted signal, and feed it back to the magnetic field feedback coil of the cesium atomic absorption chamber, so as to achieve self-excited oscillation by adjusting the frequency of the magnetic field feedback coil to be consistent with the Larmor frequency.

[0106] Figure 7 FIG. 4 is a schematic diagram showing a signal processing circuit according to an embodiment of the present invention.

[0107] According to an embodiment of the present invention, the signal processing circuit 121 may be specifically as follows: Figure 7 shown.

[0108] like Figure 7 The signal processing circuit 121 may include a preamplifier 710 , an automatic gain control subcircuit 720 , a phase shift subcircuit 730 , and a waveform shaping subcircuit 740 .

[0109] According to an embodiment of the present invention, when an external magnetic field B exists at the location of the cesium atomic absorption chamber in the cesium atomic magnetometer system, the macroscopic polarization vector of the cesium atoms in the cesium atomic absorption chamber will precess along the direction of the external magnetic field, and its precession frequency is called the Larmor frequency, and the precession frequency ,in, is the gyromagnetic ratio of the cesium atom, which is approximately At this time, if a feedback magnetic field B (t) is added perpendicular to the B direction, changing the frequency of the feedback magnetic field will change the magnitude and precession process of the polarization vector. When the feedback magnetic field frequency is equal to the Larmor frequency, the polarization vector is the largest, and the "magnetic resonance" phenomenon occurs. Among them, the feedback magnetic field B (t) is added perpendicular to the B direction through the magnetic field feedback coil of the cesium atomic absorption chamber, and the feedback magnetic field frequency is the frequency of the magnetic field feedback coil.

[0110] According to an embodiment of the present invention, the electrical signal converted by the non-magnetic photodetector 113 is input into the preamplifier 710 to amplify the electrical signal to obtain the amplified electrical signal. The automatic gain control subcircuit 720 can perform amplitude stabilization processing on the amplified electrical signal to output a sinusoidal signal. The phase shift subcircuit 730 can perform phase shift processing on the sinusoidal signal to output a phase-shifted signal, and feed the phase-shifted signal back to the magnetic field feedback coil of the cesium atomic absorption chamber to achieve self-oscillation by adjusting the frequency of the magnetic field feedback coil to be consistent with the Larmor frequency.

[0111] The frequency of the sinusoidal signal and the frequency of the phase-shifted signal are both Larmor frequencies.

[0112] According to an embodiment of the present invention, based on the preamplifier, automatic gain control subcircuit, and phase shift subcircuit in the signal processing circuit, the frequency of the magnetic field feedback coil is adjusted through positive feedback until the frequency of the magnetic field feedback coil is consistent with the Larmor frequency, thereby achieving self-oscillation, which is beneficial to high-speed tracking and measurement of the external magnetic field at the location of the cesium atomic absorption chamber in the cesium atomic magnetometer system.

[0113] According to an embodiment of the present invention, the implementation method of the above-mentioned cesium atomic magnetometer system based on dual closed-loop feedback control also includes: when realizing self-excited oscillation, using a waveform shaping subcircuit to shape the sinusoidal signal output by the automatic gain control subcircuit into a square wave signal to determine the external magnetic field value at the location of the cesium atomic absorption chamber in the cesium atomic magnetometer system.

[0114] According to an embodiment of the present invention, when self-excited oscillation is achieved, that is, when magnetic resonance occurs, the waveform shaping subcircuit can shape the sinusoidal signal output by the automatic gain control subcircuit into a square wave signal, so that the external magnetic field value at the location of the cesium atomic absorption chamber in the cesium atomic magnetometer system can be determined based on the square wave signal.

[0115] According to the embodiment of the present invention, by keeping the feedback magnetic field in the magnetic resonance state all the time, the Larmor frequency can be continuously tracked, thereby achieving the purpose of measuring the external magnetic field.

[0116] According to an embodiment of the present invention, the cesium atomic absorption chamber includes a non-magnetic heating wire, and the cesium atomic lamp includes a non-magnetic heating wire; the cesium atomic magnetometer system also includes an absorption room temperature control circuit and an atomic lamp temperature control circuit; the implementation method of the above-mentioned cesium atomic magnetometer system based on double closed-loop feedback control also includes: using the absorption room temperature control circuit to heat the cesium atomic absorption chamber through the non-magnetic heating wire in the cesium atomic absorption chamber, and controlling the temperature of the cesium atomic absorption chamber to a first preset temperature; using the atomic lamp temperature control circuit to heat the cesium atomic lamp through the non-magnetic heating wire in the cesium atomic lamp, and controlling the temperature of the cesium atomic lamp to a second preset temperature.

[0117] The temperature control module 123 may include an absorption room temperature control circuit and an atomic lamp temperature control circuit.

[0118] According to an embodiment of the present invention, both the cesium atomic absorption chamber and the cesium atomic lamp include a non-magnetic heating wire. The cesium atomic magnetometer system also includes an absorption chamber temperature control circuit and an atomic lamp temperature control circuit. The absorption chamber temperature control circuit can heat the cesium atomic absorption chamber through the non-magnetic heating wire in the cesium atomic absorption chamber, and control the temperature of the cesium atomic absorption chamber to a first preset temperature; the atomic lamp temperature control circuit can heat the cesium atomic lamp through the non-magnetic heating wire in the cesium atomic lamp, and control the temperature of the cesium atomic lamp to a second preset temperature.

[0119] The first preset temperature is the temperature that the cesium atomic absorption chamber needs to maintain, and the second preset temperature is the temperature that the cesium atomic lamp needs to maintain.

[0120] According to the embodiment of the present invention, the cesium atomic absorption chamber and the cesium atomic lamp can be controlled to maintain a constant temperature through the absorption chamber temperature control circuit and the atomic lamp temperature control circuit to avoid the influence of temperature changes.

[0121] According to an embodiment of the present invention, the absorption chamber temperature control circuit and the atomic lamp temperature control circuit both include a signal generator, an audio power amplifier, a temperature detection subcircuit and a constant temperature control subcircuit; the implementation method of the above-mentioned cesium atomic magnetometer system based on double closed-loop feedback control also includes: using the signal generator to generate an AC heating signal, and driving the non-magnetic heating wire in the cesium atomic absorption chamber through the audio power amplifier to heat the non-magnetic heating wire; using the temperature detection subcircuit to measure the real-time temperature of the non-magnetic heating wire based on the bridge principle; using the constant temperature control subcircuit to control the amplitude of the AC heating signal output by the signal generator based on the real-time temperature and the first preset temperature, so as to control the temperature of the cesium atomic absorption chamber at the first preset temperature.

[0122] Figure 8 A schematic diagram of an absorption room temperature control circuit according to an embodiment of the present invention is shown.

[0123] like Figure 8 As shown in FIG. 8 , the absorption temperature control circuit includes a signal generator 810, an audio power amplifier 820, a temperature detection subcircuit 830 and a constant temperature control subcircuit 840. The structure of the atomic lamp temperature control circuit is also shown in FIG. Figure 8 shown.

[0124] According to an embodiment of the present invention, the signal generator 810 can generate an AC heating signal and drive the non-magnetic heating wire in the cesium atomic absorption chamber 112 through the audio power amplifier 820 to heat the non-magnetic heating wire; the temperature detection subcircuit 830 can utilize the temperature change characteristics of the non-magnetic heating wire and measure the real-time temperature of the non-magnetic heating wire based on the bridge principle; the constant temperature control subcircuit 840 can control the amplitude of the AC heating signal output by the signal generator 810 to control the output power of the audio power amplifier 820 based on the real-time temperature and the first preset temperature through PI control (Proportional-Integral Controller), thereby controlling the temperature of the cesium atomic absorption chamber to the first preset temperature.

[0125] According to an embodiment of the present invention, in order to avoid interference with magnetic field measurement, an AC heating method is adopted. Moreover, since the heating wire has both heating and temperature control functions, the temperature control is realized based on the bridge principle and utilizes the characteristic that the resistance of the heating wire varies with temperature. A set of cables is used to realize the heating and temperature measurement functions at the same time, which is conducive to the simplification of the entire magnetometer probe structure.

[0126] Fig. 9 A schematic diagram of a cesium atomic magnetometer system according to an embodiment of the present invention is shown.

[0127] like Fig. 9 As shown, the cesium atomic magnetometer system includes a probe 110 and an electronics unit 120 , wherein the electronics unit includes a signal processing circuit 121 , a temperature control module 123 , a dual closed-loop radio frequency excitation circuit 122 and a power management module 124 .

[0128] According to an embodiment of the present invention, the temperature control module 123 may include an absorption room temperature control circuit 910 and an atomic lamp temperature control circuit 920. The structures of the absorption room temperature control circuit 910 and the atomic lamp temperature control circuit 920 are as follows: Figure 8 As shown, the structure of the dual closed-loop RF excitation circuit 122 is as follows Figure 4 The power management module 124 uses 24V~32V DC to supply power to the electronic unit 120.

[0129] Based on the above Fig. 9 The cesium atomic magnetometer system shown in the figure has broken through the photon shot noise limitation of the traditional open-loop technical system through the dual closed-loop feedback control technology, and solved the stability problem of the cesium atomic lamp in the conventional open-loop control; through multi-parameter control technologies such as dual gas and inner wall coating, it can not only greatly improve the Q value of the cesium atomic absorption chamber, breaking through the cesium atomic magnetic resonance line width limit under single gas control, but also greatly improve the life of the cesium atomic absorption chamber, making it possible to further improve the sensitivity of the cesium atomic magnetometer in the geomagnetic environment.

[0130] Fig.10A schematic diagram showing the sensitivity test results of a cesium atomic magnetometer according to an embodiment of the present invention is shown.

[0131] like Fig.10 As shown, the horizontal axis represents frequency (Hz), and the vertical axis represents spectral density in units of ,Right now Probe 1 is a probe of the first magnetometer, and probe 2 is a probe of the second magnetometer. The first magnetometer and the second magnetometer are as follows Fig. 9 The magnetometers shown, ie the first magnetometer and the second magnetometer, are identical, as are probes 1 and 2.

[0132] According to the embodiment of the present invention, two identical magnetometer probes can be used to form a differential method to measure the sensitivity of the magnetometer. Since the noise of the magnetometer itself is uncorrelated, while the environmental background noise is correlated, that is, the noise of the two identical magnetometers is different, the time domain data obtained by measuring the magnetic field of the two magnetometers can be subtracted to eliminate the environmental background noise, and the noise power spectrum in the frequency domain obtained after the subtraction is divided by , the intrinsic magnetic field sensitivity of each magnetometer can be obtained.

[0133] The self-power spectrum of probe 1 is the noise spectrum density curve of the probe of the first magnetometer (including environmental noise and the noise of the magnetometer itself); the self-power spectrum of probe 2 is the noise spectrum density curve of the probe of the second magnetometer (including environmental noise and the noise of the magnetometer itself); the noise spectrum is the time domain data obtained by measuring the magnetic field by probe 2 minus the time domain data obtained by measuring the magnetic field by probe 1, and the noise power spectrum in the frequency domain obtained after the subtraction is divided by The resulting noise spectral density curve is also the inherent sensitivity curve of each probe.

[0134] According to an embodiment of the present invention, Fig.10 The noise spectral density curve in FIG shows that the cesium atomic magnetometer system constructed based on the core components of the present invention such as the high-stability cesium atomic lamp and the high-Q value cesium atomic absorption chamber has a measured sensitivity of up to 100 0 ... , it is possible to achieve the measurement of Baifei-level weak magnetic fields under the geomagnetic background.

[0135] It will be appreciated by those skilled in the art that the features described in the various embodiments of the present invention may be combined and / or combined in various ways, even if such combinations or combinations are not explicitly described in the present invention. In particular, without departing from the spirit and teachings of the present invention, the features described in the various embodiments of the present invention may be combined and / or combined in various ways. All of these combinations and / or combinations fall within the scope of the present invention.

[0136] The embodiments of the present invention are described above. However, these embodiments are only for the purpose of illustration, and are not intended to limit the scope of the present invention. Although each embodiment is described above, it does not mean that the measures in each embodiment cannot be used in combination advantageously. Without departing from the scope of the present invention, those skilled in the art may make various substitutions and modifications, which should all fall within the scope of the present invention.

Claims

1. A method for implementing a cesium atomic magnetometer system based on double closed-loop feedback control, characterized in that: The cesium atomic magnetometer system includes a cesium atomic lamp and a double closed-loop radio frequency excitation circuit, the double closed-loop radio frequency excitation circuit includes a first closed-loop channel, the first closed-loop channel includes a first thermistor, a second thermistor, a first resistor voltage divider network, a second resistor voltage divider network, a voltage-controlled oscillator and a radio frequency power amplifier; the method includes: Using the first thermistor, based on the ambient temperature, to control the voltage across the first resistor divider network, wherein the first thermistor is connected in parallel with the first resistor divider network; Using the first resistor voltage divider network, based on the voltage across the first resistor voltage divider network, the output frequency of the voltage controlled oscillator is controlled, wherein the output frequency of the voltage controlled oscillator increases as the resistor voltage divider decreases; Using the second thermistor, based on the ambient temperature, to control the voltage across the second resistor voltage divider network, wherein the second thermistor is connected in parallel with the second resistor voltage divider network, and both the first thermistor and the second thermistor are negative temperature coefficient thermistors; Using the second resistor voltage divider network, based on the voltage across the second resistor voltage divider network, the output power of the RF power amplifier is controlled, wherein the output power of the RF power amplifier decreases as the resistor voltage divider decreases; and The voltage-controlled oscillator is used to output a signal of a preset frequency to the radio frequency power amplifier, and the radio frequency power amplifier is used to inject energy of the preset frequency and power output by the radio frequency power amplifier into the cesium bulb of the cesium atomic lamp to light up the cesium bulb, and the stable output of the radio frequency power amplifier is achieved by temperature compensation of the frequency and power output by the radio frequency power amplifier.

2. The method according to claim 1, characterized in that: The dual closed-loop radio frequency excitation circuit further includes a second closed-loop channel, wherein the second closed-loop channel includes the cesium atomic lamp, the radio frequency power amplifier and the photoelectric detector, and the method further includes: The photoelectric detector is used to monitor the power of the light emitted by the cesium atomic lamp in real time and feed it back to the radio frequency power amplifier to adjust the output power of the radio frequency power amplifier based on the power of the light emitted by the cesium atomic lamp and the preset optical power, so that the cesium atomic lamp can output optical power stably.

3. The method according to claim 1, characterized in that The cesium atomic magnetometer system further includes an optical component; the optical component includes a collimating lens, a filter, and a combined circular polarizer; the method further includes: Using the collimating lens, collimating the light emitted by the cesium bulb, and outputting the collimated light; Using the filter, filtering the collimated light to output light of a target wavelength; and The combined circular polarizer is used to perform polarization processing on the light of the target wavelength and output circularly polarized pump light.

4. The method according to claim 3, characterized in that The cesium atomic magnetometer system further includes a cesium atomic absorption chamber; the method further includes: The circularly polarized pump light is incident on the cesium atomic absorption chamber; The cesium atomic absorption chamber is filled with cesium single substance, and is also filled with buffer gas to reduce spin-destructive collisions between cesium atoms and the inner wall of the cesium atomic absorption chamber; the cesium atomic absorption chamber is also filled with quenching gas to avoid reabsorption and reradiation of spontaneously radiated photons with cesium atoms before exiting the cesium atomic absorption chamber; the inner wall of the cesium atomic absorption chamber is coated with an aluminum oxide film to reduce the diffusion rate of cesium atoms to the inner wall of the cesium atomic absorption chamber.

5. The method according to claim 4, characterized in that The buffer gas includes methane and the quench gas includes nitrogen.

6. The method according to claim 4, characterized in that The optical assembly further comprises a focusing lens and a non-magnetic photodetector; the method further comprises: The focusing lens is used to focus the light outputted from the cesium atomic absorption chamber, and the focused light is outputted to be incident on the photosensitive surface of the non-magnetic photodetector; The focused light is converted into an electrical signal by using the non-magnetic photodetector.

7. The method according to claim 6, characterized in that The cesium atomic magnetometer system further includes a signal processing circuit, which includes a preamplifier, an automatic gain control subcircuit, a phase shift subcircuit and a waveform shaping subcircuit; the method further includes: Amplifying the electrical signal using the preamplifier and outputting the amplified electrical signal; Using the automatic gain control subcircuit, the amplified electrical signal is subjected to amplitude stabilization processing to output a sinusoidal signal, wherein the frequency of the sinusoidal signal is the Larmor frequency; The phase shift subcircuit is used to perform phase shift processing on the sinusoidal signal, output the phase-shifted signal, and feed it back to the magnetic field feedback coil of the cesium atomic absorption chamber, so as to achieve self-oscillation by adjusting the frequency of the magnetic field feedback coil to be consistent with the Larmor frequency.

8. The method according to claim 7, characterized in that Also includes: In the case of realizing self-excited oscillation, the waveform shaping subcircuit is used to shape the sinusoidal signal output by the automatic gain control subcircuit into a square wave signal to determine the external magnetic field value at the location of the cesium atomic absorption chamber in the cesium atomic magnetometer system.

9. The method according to claim 4, characterized in that The cesium atomic absorption chamber includes a non-magnetic heating wire, and the cesium atomic lamp includes a non-magnetic heating wire; the cesium atomic magnetometer system also includes an absorption chamber temperature control circuit and an atomic lamp temperature control circuit; the method also includes: Using the absorption room temperature control circuit, the cesium atomic absorption chamber is heated through the non-magnetic heating wire in the cesium atomic absorption chamber, and the temperature of the cesium atomic absorption chamber is controlled to a first preset temperature; and The cesium atomic lamp is heated by the atomic lamp temperature control circuit through the non-magnetic heating wire in the cesium atomic lamp, and the temperature of the cesium atomic lamp is controlled at a second preset temperature.

10. The method according to claim 9, characterized in that The absorption room temperature control circuit and the atomic lamp temperature control circuit both include a signal generator, an audio power amplifier, a temperature detection subcircuit and a constant temperature control subcircuit; the method further includes: Using the signal generator to generate an AC heating signal, and driving the non-magnetic heating wire in the cesium atomic absorption chamber through the audio power amplifier to heat the non-magnetic heating wire; Using the temperature detection subcircuit, based on the bridge principle, the real-time temperature of the non-magnetic heating wire is measured; and The constant temperature control subcircuit is used to control the amplitude of the AC heating signal output by the signal generator based on the real-time temperature and the first preset temperature, so as to control the temperature of the cesium atomic absorption chamber at the first preset temperature.

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