Laser stable power control device for array atom magnetometer and control method of laser stable power control device

Abstract

The invention relates to the technical field of semiconductor laser control, and discloses a laser stable power control device for an array atom magnetometer and a control method of the laser stable power control device. The laser light splitting optical path is arranged at the output end of the amplification laser; the double-ring active anti-interference stable power control board card is connected with a photoelectric detector in the laser light splitting light path, and the double-ring active anti-interference stable power control board card is used for receiving a light power signal of the measuring light provided by the laser light splitting light path so as to obtain the magnitude of compensation current needed by an amplification laser; the digital laser controller is used for injecting current into the amplification laser and controlling the temperature of the amplification laser; the beam splitter is connected with one end, far away from the amplification laser, of the laser splitting light path; and the array type atom magnetometer is used for carrying out array type measurement on a space magnetic field. The power stability of the amplification laser is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor laser control, and in particular to a laser power stabilization control device for an array atomic magnetometer and a control method thereof. Background Art

[0002] Brain magnetic imaging technology based on array atomic magnetometers has demonstrated significant application value in the study of brain behavior and cognition, as well as in the clinical diagnosis of psychiatric disorders. This technology typically employs a light source solution that splits the output light of an amplified laser to enhance the consistency of performance across magnetometers. However, when operating in an open-loop state, amplified lasers are affected by factors such as device aging, random vibration, and temperature drift, resulting in output power instabilities such as jitter and slow drift, which ultimately degrade the performance of the array atomic magnetometer.

[0003] The laser power stabilization control methods proposed in previous studies have the following main shortcomings: First, they rely on complex optical path structures, which complicates the multi-channel integration of atomic magnetometers and makes them inconvenient to use in clinical medical scenarios outside the laboratory; second, the target control object is the low-power laser in the single-channel magnetometer, and the actual performance on the high-power amplified laser is poor; third, the disturbance that affects the laser performance is not filtered out, and the long-term stability of the output optical power of the amplified laser is poor.

[0004] Therefore, it is necessary to provide a laser power stabilization control device and a control method thereof for an array atomic magnetometer to solve the problems in the prior art. Summary of the Invention

[0005] In view of this, the present invention proposes a laser power stabilization control device and control method for an array atomic magnetometer, aiming to solve the problem of long-term power stability control at high-power operating points that cannot be solved by current laser power stabilization control technology, and to weaken the noise in the output optical power through a control structure with a dual-loop extended state observer, thereby achieving improvements in the short-term and long-term performance of the output optical power of the amplified laser.

[0006] On the one hand, the present invention provides a laser power stabilization control device for an array atomic magnetometer, comprising:

[0007] An amplified laser, comprising a seed source and a tapered amplifier, wherein the tapered amplifier is arranged at the output end of the seed source and is used to amplify the power of the laser light emitted by the seed source and output the amplified laser light as a light source of an array atomic magnetometer;

[0008] A laser splitting optical path is provided at the output end of the amplifying laser;

[0009] A dual-loop active anti-interference and power stabilization control board is connected to the photodetector in the laser splitting optical path. The dual-loop active anti-interference and power stabilization control board is used to receive the optical power signal of the measurement light provided by the laser splitting optical path to obtain the compensation current required for the amplified laser;

[0010] A digital laser controller is used to inject current into the amplifying laser and control the temperature of the amplifying laser, wherein the input end of the modulation voltage of one current source of the digital laser is connected to the output end of the dual-loop active anti-disturbance and power stabilization control board to receive the magnitude of the current to be compensated transmitted by the digital laser controller;

[0011] A beam splitter connected to an end of the laser splitting optical path away from the amplifying laser;

[0012] An array atomic magnetometer is connected to the output end of the beam splitter, and receives the pump light provided by the laser splitting optical path to perform array measurement of the spatial magnetic field.

[0013] Furthermore, the laser beam splitting optical path includes:

[0014] a magneto-optical isolator, the input end of which is connected to the output end of the tapered amplifier;

[0015] a shaping prism, an input end of which is connected to the output end of the magneto-optical isolator;

[0016] A beam splitter prism, the input end of which is connected to the output end of the shaping prism, and the beam splitter prism includes two output ends;

[0017] an optical fiber coupler, the input end of which is connected to one of the output ends of the beam splitter prism, and the output end of the optical fiber coupler is connected to the input end of the beam splitter;

[0018] The input end of the photodetector is connected to the other output end of the beam splitter prism, and the output end of the photodetector is connected to the input end of the dual-loop active anti-disturbance and power stabilization control board.

[0019] Furthermore, the dual-loop active anti-interference and power stabilization control board includes an optical power measurement value and set value input interface and a microcontroller that implements the dual-loop active anti-interference and power stabilization control algorithm function.

[0020] Furthermore, the digital laser controller includes:

[0021] Two independently working thermoelectric coolers drive two independently working current sources, and the current sources are voltage modulated current sources;

[0022] The output end driven by one of the thermoelectric coolers is connected to the input end of the thermoelectric cooler at the lower portion of the seed source, and the output end driven by the other thermoelectric cooler is connected to the input end of the thermoelectric cooler at the lower portion of the tapered amplifier.

[0023] One current source provides injection current to the seed source according to a set value; the other current source provides injection current to the tapered amplifier according to a set value, and receives the output of the dual-loop active anti-interference and power stabilization control board card to superimpose the compensation current required for power stabilization on the basis of the injection current.

[0024] Furthermore, the microcontroller includes an inner observer and an outer observer;

[0025] The inner observer is used to observe the disturbance introduced by the inaccurate model parameters, and the outer observer observes the noise introduced by the optical power measurement end.

[0026] Furthermore, the model order and input gain of the inner observer are determined according to the high-frequency small signal model of the voltage-modulated current source in the digital laser controller and the poles and zeros of the photodetector in the laser splitting optical path.

[0027] Furthermore, the outer observer includes a multi-stage extended state observer, and the multi-stage extended state observer is cascaded;

[0028] The bandwidth of each stage of the expanded state observer increases with the increase of the number of stages. The outer observer synthesizes the estimated value of the state variable of the laser power stabilization control device according to the output of each stage of the expanded state observer.

[0029] Furthermore, the control law utilizes the observation results of the inner observer to suppress the disturbance introduced by inaccurate model parameters, and utilizes the observation results of the outer observer to suppress the influence of noise introduced by optical power measurement.

[0030] Compared with the prior art, the beneficial effect of the present invention is that by adopting a dual-loop active anti-disturbance and power stabilization control board, the power stability of the amplified laser is significantly improved, and its effect is better than the traditional PID algorithm. Experimental results show that compared with the use of the standard active anti-disturbance control algorithm, the fluctuation of the optical power of the amplified laser within 1 hour is reduced from 0.63% to 0.05%, and the Allan variance over 100 seconds is reduced to 1 / 10. The present invention shows excellent performance in suppressing optical power noise and slow drift, and is particularly suitable for application scenarios such as array atomic magnetometers that require high-power, high-stability laser light sources.

[0031] On the other hand, the present application also provides a control method for a laser power stabilization control device for an array atomic magnetometer, comprising:

[0032] The control object of the inner loop in the dual-loop active anti-disturbance and stable power control board is modeled. By analyzing the high-frequency small signal model of the amplified laser peripheral circuit, the control voltage u of the voltage-modulated current source is converted into a CTL is the input and measured optical power signal u PWR The output controlled object is established as a third-order model:

[0033]

[0034] In the above formula, i O is the current source output; φ AL is the proportional coefficient of the optical power signal and the output current of the current source; G a (s) is the open-loop transfer function of the voltage-modulated current source; G f (s) is the transfer function of the feedback loop; μ OA is the open-loop gain of the operational amplifier; R OAH 、C OAH are the resistance and capacitance values ​​of the high-frequency pole of the operational amplifier; R OAL 、C OAL are the resistance and capacitance values ​​of the low-frequency pole of the operational amplifier; R c 、C c are the resistance and capacitance between the operational amplifier and NMOS respectively; C′ gs is the gate-source capacitance of NMOS; g m is the NMOS drain-source transconductance; s represents the complex frequency; α0, α1, α2, and α3 represent the s in the denominator of the transfer function. 0 Item, s item, s 2 Item, s 3 The coefficient before R f Represents the feedback resistance between NMOS and power supply;

[0035] From this, we can obtain the state space equation of the inner loop control object with expanded state:

[0036]

[0037] In the above formula, x is the inner loop expansion state vector; A is the state matrix of the system; u in is the output of the inner loop controller; F is the generalized disturbance; y in is the output of the inner loop controlled object; is the gain of the inner loop controller; b, c, d are the unit vectors that vectorize the state equation; represents the derivatives of the inner loop expansion state vector and the generalized perturbation. The specific expressions of each parameter are as follows. For this application scenario, n = 3:

[0038]

[0039] Furthermore, we can obtain an estimate of the inner loop expansion state vector The calculation formula is:

[0040]

[0041] In the above formula, represents the estimate of the inner loop expansion state vector The time derivative of in is the bandwidth of the inner loop extended state observer; L is the inner loop controller gain vector; γ m is the gain coefficient, m=1,2,3,…n+1; n represents the system order; m represents the sequence number of the gain coefficient in L; u in represents the output of the inner loop controller;

[0042] The outer loop extended state observer is composed of a cascade of several extended state observers with gradually increasing bandwidths:

[0043]

[0044] In the above formula, ξ i is the observation result of the outer loop expansion state observer at layer i, is its derivative with respect to time, The observation results synthesized by all outer loop expansion state observers have the same dimension as the inner loop consistent; y out is the output of the outer loop controlled object; u out is the output of the outer loop controller; is the gain of the outer loop controller; l i is the gain vector of the outer loop controller of the i-th layer; ω oi is the bandwidth of the i-th layer outer loop extended state observer; k is the observation result of the k-th outer loop expansion state observer; ξ p is the observation result of the p-th layer outer loop expanded state observer; p is the total number of layers of the outer loop expanded state observer; n represents the system order;

[0045] Finally, the specific expressions of the control laws corresponding to the inner and outer loop controllers are obtained:

[0046]

[0047] In the above formula, K out is the gain vector of the outer loop controller; ω c is the bandwidth of the outer loop controller; κ l is the gain coefficient; l is a certain gain coefficient in K out The serial number in is l=2,3,…n; n represents the system order;

[0048] The control law is implemented through a microcontroller or other processor, and the output result of the control law is added to the input end of the voltage-modulated current source in the amplifying laser, so as to achieve stable power control of the amplifying laser.

[0049] The control law is implemented through a microcontroller or other processor, and the output result of the control law is added to the input end of the voltage-modulated current source in the amplifying laser, so as to achieve stable power control of the amplifying laser.

[0050] It is understandable that the laser power stabilization control device and control method for an array atomic magnetometer provided in the present application have the same beneficial effects and will not be described in detail here. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Various other advantages and benefits will become apparent to those skilled in the art upon reading the detailed description of the preferred embodiment below. The accompanying drawings are for illustration purposes only and are not to be considered as limiting the present invention. The same reference symbols are used throughout the drawings to represent the same components. In the drawings:

[0052] Figure 1 A structural block diagram of a laser power stabilization control device for an array atomic magnetometer provided in an embodiment of the present invention;

[0053] Figure 2(a) is a schematic diagram of the driving principle of the amplified laser;

[0054] Figure 2(b) is the schematic diagram of the high-frequency small-signal model;

[0055] Figure 3 A flowchart of a control method for a laser power stabilization control device for an array atomic magnetometer provided by an embodiment of the present invention;

[0056] Figure 4 A performance comparison chart of the dual-loop active disturbance rejection and power stabilization algorithm provided by an embodiment of the present invention and the standard active disturbance rejection and power stabilization algorithm at different laser operating points in terms of fluctuation amount;

[0057] Figure 5 This is a performance comparison chart of the dual-loop active disturbance rejection and power stabilization control algorithm provided by an embodiment of the present invention and the standard active disturbance rejection and power stabilization control algorithm in terms of Allan variance. DETAILED DESCRIPTION

[0058] Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art. It should be noted that, unless there is a conflict, the embodiments of the present disclosure and the features in the embodiments can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in conjunction with the embodiments.

[0059] In some embodiments of this application, see Figure 1 As shown, this embodiment provides a laser power stabilization control device for an array atomic magnetometer, comprising:

[0060] An amplified laser, comprising a seed source and a tapered amplifier, wherein the tapered amplifier is arranged at the output end of the seed source and is used to amplify the power of the laser light emitted by the seed source and output the amplified laser light as a light source of an array atomic magnetometer;

[0061] A laser splitting optical path is provided at the output end of the amplifying laser;

[0062] A dual-loop active anti-interference and power stabilization control board is connected to the photodetector in the laser splitting optical path. The dual-loop active anti-interference and power stabilization control board is used to receive the optical power signal of the measurement light provided by the laser splitting optical path to obtain the compensation current required for the amplified laser;

[0063] A digital laser controller is used to inject current into the amplifying laser and control the temperature of the amplifying laser, wherein the input end of the modulation voltage of one current source of the digital laser is connected to the output end of the dual-loop active anti-disturbance and power stabilization control board to receive the magnitude of the current to be compensated transmitted by the digital laser controller;

[0064] A beam splitter connected to an end of the laser splitting optical path away from the amplifying laser;

[0065] An array atomic magnetometer is connected to the output end of the beam splitter, and receives the pump light provided by the laser splitting optical path to perform array measurement of the spatial magnetic field.

[0066] It can be understood that by adopting the dual-loop active anti-disturbance and power stabilization control board, the power stability of the amplified laser is significantly improved, and its effect is better than the traditional PID algorithm. Experimental results show that compared with the use of the standard active anti-disturbance control algorithm, the fluctuation of the optical power of the amplified laser within 1 hour is reduced from 0.63% to 0.05%, and the Allan variance over 100 seconds is reduced to 1 / 10. The present invention shows excellent performance in suppressing optical power noise and slow drift, and is particularly suitable for application scenarios such as array atomic magnetometers that require high-power, high-stability laser light sources. Furthermore, Figure 4 A performance comparison chart of the dual-loop active disturbance rejection and power stabilization algorithm provided by an embodiment of the present invention and the standard active disturbance rejection and power stabilization algorithm at different laser operating points in terms of fluctuation amount; Figure 5 This is a performance comparison chart of the dual-loop active disturbance rejection and power stabilization control algorithm provided by an embodiment of the present invention and the standard active disturbance rejection and power stabilization control algorithm in terms of Allan variance.

[0067] Specifically, the laser output from the seed source is power-amplified by a tapered amplifier, and the power amplification ratio can be adjusted by adjusting the injection current of the tapered amplifier.

[0068] In some embodiments of the present application, the laser beam splitting optical path includes:

[0069] a magneto-optical isolator, the input end of which is connected to the output end of the tapered amplifier;

[0070] a shaping prism, an input end of which is connected to the output end of the magneto-optical isolator;

[0071] A beam splitter prism, the input end of which is connected to the output end of the shaping prism, and the beam splitter prism includes two output ends;

[0072] an optical fiber coupler, the input end of which is connected to one of the output ends of the beam splitter prism, and the output end of the optical fiber coupler is connected to the input end of the beam splitter;

[0073] The input end of the photodetector is connected to the other output end of the beam splitter prism, and the output end of the photodetector is connected to the input end of the dual-loop active anti-disturbance and power stabilization control board.

[0074] Specifically, the laser splitting optical path is used to split the laser output by the amplified laser into two beams according to a constant power ratio. The laser splitting optical path includes a magneto-optical isolator, a shaping prism, a splitting prism, a fiber coupler and a photodetector. The stronger beam of light is used to drive an array atomic magnetometer or other equipment, and the weaker beam of light is converted into an electrical signal by the photodetector and input into the dual-loop active anti-interference and power stabilization control board.

[0075] In some embodiments of the present application, the dual-loop active interference rejection and power stabilization control board includes an optical power measurement value and set value input interface and a microcontroller that implements the dual-loop active interference rejection and power stabilization control algorithm function.

[0076] In some embodiments of the present application, the digital laser controller includes:

[0077] Two independently working thermoelectric coolers drive two independently working current sources, and the current sources are voltage modulated current sources;

[0078] The output end driven by one of the thermoelectric coolers is connected to the input end of the thermoelectric cooler at the lower portion of the seed source, and the output end driven by the other thermoelectric cooler is connected to the input end of the thermoelectric cooler at the lower portion of the tapered amplifier.

[0079] One current source provides injection current to the seed source according to a set value; the other current source provides injection current to the tapered amplifier according to a set value, and receives the output of the dual-loop active anti-interference and power stabilization control board card to superimpose the compensation current required for power stabilization on the basis of the injection current.

[0080] Specifically, the digital laser controller includes two independent voltage-controlled current sources and two independent temperature control modules, and the operating points of the corresponding parameters can be configured separately on the host computer interface.

[0081] In some embodiments of the present application, the microcontroller includes an inner observer and an outer observer;

[0082] The inner observer is used to observe the disturbance introduced by the inaccurate model parameters, and the outer observer is used to observe the noise introduced by the optical power measurement end.

[0083] In some embodiments of the present application, the model order and input gain of the inner observer are determined based on the high-frequency small signal model of the voltage-modulated current source in the digital laser controller and the zero poles of the photodetector in the laser splitting optical path.

[0084] In some embodiments of the present application, the outer observer includes a multi-stage extended state observer, and the multi-stage extended state observer is cascaded;

[0085] The bandwidth of each stage of the expanded state observer increases with the increase of the number of stages. The outer observer synthesizes the estimated value of the state variable of the laser power stabilization control device according to the output of each stage of the expanded state observer.

[0086] In some embodiments of the present application, the control law utilizes the observation results of the inner observer to suppress the disturbance introduced by inaccurate model parameters, and utilizes the observation results of the outer observer to suppress the noise introduced by optical power measurement; thereby improving the long-term stability of the laser output power.

[0087] On the other hand, see Figure 3 The present application also provides a control method for a laser power stabilization control device for an array-type atomic magnetometer, which is applied to the above-mentioned laser power stabilization control device for an array-type atomic magnetometer, comprising:

[0088] The control object of the inner loop in the dual-loop active anti-disturbance and stable power control board is modeled. By analyzing the high-frequency small signal model of the amplified laser peripheral circuit, the control voltage u of the voltage-modulated current source is converted into a CTL is the input and measured optical power signal u PWR The output controlled object is established as a third-order model:

[0089]

[0090] In the above formula, i O is the current source output; φ AL is the proportional coefficient of the optical power signal and the output current of the current source; G a (s) is the open-loop transfer function of the voltage-modulated current source; G f (s) is the transfer function of the feedback loop; μ OA is the open-loop gain of the operational amplifier; R OAH 、C OAH are the resistance and capacitance values ​​of the high-frequency pole of the operational amplifier; R OAL 、C OAL are the resistance and capacitance values ​​of the low-frequency pole of the operational amplifier; R c 、C c are the resistance and capacitance between the operational amplifier and NMOS respectively; C′ gs is the gate-source capacitance of NMOS; g m is the NMOS drain-source transconductance; s represents the complex frequency; α0, α1, α2, and α3 represent the s in the denominator of the transfer function. 0 Item, s item, s 2 Item, s 3 The coefficient before R f Represents the feedback resistance between NMOS and power supply;

[0091] From this, we can obtain the state space equation of the inner loop control object with expanded state:

[0092]

[0093] In the above formula, x is the inner loop expansion state vector; A is the state matrix of the system; u in is the output of the inner loop controller; F is the generalized disturbance; y in is the output of the inner loop controlled object; is the gain of the inner loop controller; b, c, d are the unit vectors that vectorize the state equation; represents the derivatives of the inner loop expansion state vector and the generalized perturbation. The specific expressions of each parameter are as follows. For this application scenario, n = 3:

[0094]

[0095] Furthermore, we can obtain an estimate of the inner loop expansion state vector The calculation formula is:

[0096]

[0097] In the above formula, represents the estimate of the inner loop expansion state vector The time derivative of in is the bandwidth of the inner loop extended state observer; L is the inner loop controller gain vector; γ m is the gain coefficient, m=1,2,3,…n+1; n represents the system order; m represents the sequence number of the gain coefficient in L; u in represents the output of the inner loop controller;

[0098] The outer loop extended state observer is composed of a cascade of several extended state observers with gradually increasing bandwidths:

[0099]

[0100] In the above formula, ξ i is the observation result of the outer loop expansion state observer at layer i, is its derivative with respect to time, The observation results synthesized by all outer loop expansion state observers have the same dimension as the inner loop consistent; y out is the output of the outer loop controlled object; u out is the output of the outer loop controller; is the gain of the outer loop controller; l i is the gain vector of the outer loop controller of the i-th layer; ω oi is the bandwidth of the i-th layer outer loop extended state observer; k is the observation result of the k-th outer loop expansion state observer; ξ p is the observation result of the p-th layer outer loop expanded state observer; p is the total number of layers of the outer loop expanded state observer; n represents the system order;

[0101] Finally, the specific expressions of the control laws corresponding to the inner and outer loop controllers are obtained:

[0102]

[0103] In the above formula, K out is the gain vector of the outer loop controller; ω c is the bandwidth of the outer loop controller; κ l is the gain coefficient; l is a certain gain coefficient in K out The serial number in is l=2,3,…n; n represents the system order;

[0104] The control law is implemented through a microcontroller or other processor, and the output result of the control law is added to the input end of the voltage-modulated current source in the amplifying laser, so as to achieve stable power control of the amplifying laser.

[0105] Among them, Figure 2 is the modeling principle diagram of the inner loop control object, Figure 2(a) is the amplified laser driving principle diagram, and Figure 2(b) is the high-frequency small signal model principle diagram.

[0106] In summary, the use of a dual-loop active anti-disturbance and power stabilization control board significantly improves the power stability of the amplified laser, and its effect is better than that of the traditional PID algorithm. Experimental results show that compared with the use of a standard active anti-disturbance control algorithm, the fluctuation of the optical power of the amplified laser within 1 hour is reduced from 0.63% to 0.05%, and the Allan variance over 100 seconds is reduced to 1 / 10. The present invention exhibits excellent performance in suppressing optical power noise and slow drift, and is particularly suitable for application scenarios such as array atomic magnetometers that require high-power, high-stability laser light sources.

[0107] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may take the form of a complete hardware embodiment, a complete software embodiment, or a combination of software and hardware embodiments. Furthermore, the present application may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0108] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems) and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the 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 generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0109] 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 work in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0110] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions executed on the computer or other programmable device for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0111] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the field should understand that the specific implementation methods of the present invention can still be modified or replaced by equivalents. Any modification or equivalent replacement that does not depart from the spirit and scope of the present invention should be covered by the scope of protection of the claims of the present invention.

Claims

1. A laser power stabilization control device for an array atomic magnetometer, characterized in that: include: An amplified laser, comprising a seed source and a tapered amplifier, wherein the tapered amplifier is arranged at the output end of the seed source and is used to amplify the power of the laser light emitted by the seed source and output the amplified laser light as a light source of an array atomic magnetometer; A laser splitting optical path is provided at the output end of the amplifying laser; A dual-loop active anti-interference and power stabilization control board is connected to the photodetector in the laser splitting optical path. The dual-loop active anti-interference and power stabilization control board is used to receive the optical power signal of the measurement light provided by the laser splitting optical path to obtain the compensation current required for the amplified laser; A digital laser controller is used to inject current into the amplifying laser and control the temperature of the amplifying laser, wherein the input end of the modulation voltage of one current source of the digital laser is connected to the output end of the dual-loop active anti-disturbance and power stabilization control board to receive the magnitude of the current to be compensated transmitted by the digital laser controller; A beam splitter connected to an end of the laser splitting optical path away from the amplifying laser; An array atomic magnetometer is connected to the output end of the beam splitter, and receives the pump light provided by the laser splitting optical path to perform array measurement of the spatial magnetic field.

2. The laser power stabilization control device for an array atomic magnetometer according to claim 1, characterized in that: The laser beam splitting optical path includes: a magneto-optical isolator, the input end of which is connected to the output end of the tapered amplifier; a shaping prism, an input end of which is connected to the output end of the magneto-optical isolator; A beam splitter prism, the input end of which is connected to the output end of the shaping prism, and the beam splitter prism includes two output ends; an optical fiber coupler, the input end of which is connected to one of the output ends of the beam splitter prism, and the output end of the optical fiber coupler is connected to the input end of the beam splitter; The input end of the photodetector is connected to the other output end of the beam splitter prism, and the output end of the photodetector is connected to the input end of the dual-loop active anti-disturbance and power stabilization control board.

3. The laser power stabilization control device for an array atomic magnetometer according to claim 2, characterized in that: The dual-loop active anti-interference and power stabilization control board includes an optical power measurement value and a set value input interface and a microcontroller that implements the dual-loop active anti-interference and power stabilization control algorithm function.

4. The laser power stabilization control device for an array atomic magnetometer according to claim 3, characterized in that: The digital laser controller comprises: Two independently working thermoelectric coolers drive two independently working current sources, and the current sources are voltage modulated current sources; The output end driven by one of the thermoelectric coolers is connected to the input end of the thermoelectric cooler at the lower portion of the seed source, and the output end driven by the other thermoelectric cooler is connected to the input end of the thermoelectric cooler at the lower portion of the tapered amplifier. One current source provides injection current to the seed source according to a set value; the other current source provides injection current to the tapered amplifier according to a set value, and receives the output of the dual-loop active anti-interference and power stabilization control board card to superimpose the compensation current required for power stabilization on the basis of the injection current.

5. The laser power stabilization control device for an array atomic magnetometer according to claim 3, characterized in that: The microcontroller includes an inner observer and an outer observer; The inner observer is used to observe the disturbance introduced by the inaccurate model parameters, and the outer observer observes the noise introduced by the optical power measurement end.

6. The laser power stabilization control device for an array atomic magnetometer according to claim 5, characterized in that: The model order and input gain of the inner observer are determined according to the high-frequency small signal model of the voltage-modulated current source in the digital laser controller and the poles and zeros of the photodetector in the laser splitting optical path.

7. The laser power stabilization control device for an array atomic magnetometer according to claim 6, characterized in that: The outer observer includes a multi-stage extended state observer, and the multi-stage extended state observer is cascaded; The bandwidth of each stage of the expanded state observer increases with the increase of the number of stages. The outer observer synthesizes the estimated value of the state variable of the laser power stabilization control device according to the output of each stage of the expanded state observer.

8. The laser power stabilization control device for an array atomic magnetometer according to claim 7, characterized in that: The control law uses the observation results of the inner observer to suppress the disturbance introduced by inaccurate model parameters, and uses the observation results of the outer observer to suppress the influence of noise introduced by optical power measurement.

9. A control method for a laser power stabilization control device for an array-type atomic magnetometer, applied to the laser power stabilization control device for an array-type atomic magnetometer according to any one of claims 1 to 8, characterized in that: include: The control object of the inner loop in the dual-loop active anti-disturbance and stable power control board is modeled. By analyzing the high-frequency small signal model of the amplified laser peripheral circuit, the control voltage u of the voltage-modulated current source is converted into a CTL is the input and measured optical power signal u PWR The output controlled object is established as a third-order model: In the above formula, i O is the current source output; φ AL is the proportional coefficient of the optical power signal and the output current of the current source; G a (s) is the open-loop transfer function of the voltage-modulated current source; G f (s) is the transfer function of the feedback loop; μ OA is the open-loop gain of the operational amplifier; R OAH 、C OAH are the resistance and capacitance values ​​of the high-frequency pole of the operational amplifier; R OAL 、C OAL are the resistance and capacitance values ​​of the low-frequency pole of the operational amplifier; R c 、C c are the resistance and capacitance between the operational amplifier and NMOS respectively; C′ gs is the gate-source capacitance of NMOS; g m is the NMOS drain-source transconductance; s represents the complex frequency; α0, α1, α2, and α3 represent the s in the denominator of the transfer function. 0 Item, s item, s 2 Item, s 3 The coefficient before R f Represents the feedback resistance between NMOS and power supply; From this, we can obtain the state space equation of the inner loop control object with expanded state: In the above formula, x is the inner loop expansion state vector; A is the state matrix of the system; u in is the output of the inner loop controller; F is the generalized disturbance; y in is the output of the inner loop controlled object; is the gain of the inner loop controller; b, c, d are the unit vectors that vectorize the state equation; They represent the inner loop expansion state vector and the derivatives corresponding to the generalized perturbation respectively. The specific expressions of each parameter are as follows. For this application scenario, n = 3: Furthermore, we can obtain an estimate of the inner loop expansion state vector The calculation formula is: In the above formula, represents the estimate of the inner loop expansion state vector The time derivative of in is the bandwidth of the inner loop extended state observer; L is the inner loop controller gain vector; γ m is the gain coefficient, m=1,2,3,…n+1; n represents the system order; m represents the sequence number of the gain coefficient in L; u in represents the output of the inner loop controller; The outer loop extended state observer is composed of a cascade of several extended state observers with gradually increasing bandwidths: In the above formula, ξ i is the observation result of the outer loop expansion state observer at layer i, for ξ i The time derivative, The observation results synthesized by all outer loop expansion state observers have the same dimension as the inner loop consistent; y out is the output of the outer loop controlled object; u out is the output of the outer loop controller; is the gain of the outer loop controller; l i is the gain vector of the outer loop controller of the i-th layer; ω oi is the bandwidth of the i-th layer outer loop extended state observer; k is the observation result of the k-th outer loop expansion state observer; ξ p is the observation result of the p-th layer outer loop expanded state observer; p is the total number of layers of the outer loop expanded state observer; n represents the system order; Finally, the specific expressions of the control laws corresponding to the inner and outer loop controllers are obtained: In the above formula, K out is the gain vector of the outer loop controller; ω c is the bandwidth of the outer loop controller; κ l is the gain coefficient; l is a certain gain coefficient in K out The serial number in is l=2,3,…n; n represents the system order; The control law is implemented through a microcontroller or other processor, and the output result of the control law is added to the input end of the voltage-modulated current source in the amplifying laser, so as to achieve stable power control of the amplifying laser.

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