Magnetic resonance phase compensation method and system based on external signal compensation

Abstract

The application provides a magnetic resonance phase compensation method and system based on external signal compensation, and the method comprises the following steps: multiplying sigRef and sigA to obtain a noise signal sigNoise; changing the frequency of an externally applied signal, adding a noise signal consistent with sigNoise to the external magnetic field signal sigRef; through PID closed loop control, the error of the calculation signal is suppressed to a fixed value or 0; multiplying the adjusted sigRef+sigNoise and the optical signal sigB to demodulate, so as to suppress the sigNoise contained in the optical signal sigB, and the result of the calculation at this time is the signal of the atomic nucleus spin, that is, the actual required signal; according to the multiplication result of the optical signal sigA and the adjusted sigRef+sigNoise, the output frequency of the detection laser is controlled through PID closed loop control, and the phase noise of the detection laser is suppressed. The technical scheme of the application is used to solve the technical problems that the single forced laser output light intensity stabilization method in the prior art is relatively single, the implementation means is relatively complicated, and the development trend of the sensor is small in size.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of quantum sensing technology, and in particular to a magnetic resonance phase compensation method and system based on external signal compensation. BACKGROUND

[0002] The magnetic resonance phase under the atomic spin ensemble state is an important working parameter of some atomic sensors such as nuclear magnetic resonance gyroscopes. The current detection means mainly realizes the detection of the magnetic resonance phase under the atomic spin ensemble state through a laser and a photoelectric detector. In this case, in order to improve the sensitivity of the sensor, it is necessary to improve the sensitivity of the detection means. In order to improve the detection sensitivity, the core element is to ensure the stability of the detection laser and reduce the influence of the noise of the detection laser on the detection means.

[0003] The influence of the detection laser on the atomic signal of the atomic magnetic resonance state mainly has two aspects, one is the pumping noise and the magnetic field noise, and the other is the noise of the detection laser. The intensity of the detection laser affects the signal intensity of the atom under the atomic spin ensemble state, and the phase noise of the detection laser mainly affects the magnetic resonance phase under the atomic spin ensemble state. Therefore, when the actual laser is used to detect the magnetic resonance phase under the atomic spin ensemble state, it is necessary to suppress the magnetic field noise and the pumping light noise, and to reduce the influence of the phase noise of the detection laser on the magnetic resonance phase, so as to ensure the stability of the sensor and realize the precise measurement with high sensitivity.

[0004] At present, the commonly used laser for detecting the magnetic resonance phase under the atomic spin ensemble state is mainly a semiconductor laser. The semiconductor laser has small volume, high output power and strong light intensity focusing ability. The requirements of high-sensitivity magnetic resonance phase detection on the laser are becoming higher and higher. Under the premise of pursuing small volume of the atomic sensor, the single method of forcing the laser to output stable light intensity is relatively single, and the implementation means is relatively complicated, which is contrary to the development trend of the small volume sensor. Therefore, suppressing the influence of the phase noise of the laser on the magnetic resonance phase is one of the important ways to improve the sensitivity of the atomic sensor. SUMMARY

[0005] The present application provides a magnetic resonance phase compensation method and system based on external signal compensation, which can solve the technical problems of the prior art that the single method of forcing the laser to output stable light intensity is relatively single, and the implementation means is relatively complicated, which is contrary to the development trend of the small volume sensor.

[0006] According to an aspect of the present application, a magnetic resonance phase compensation method based on external signal compensation is provided, characterized in that the magnetic resonance phase compensation method based on external signal compensation comprises: setting an atomic cell A and an atomic cell B, the atomic cell B containing inert gas and isotope atomic nuclei and electrons, the atomic cell A containing only inert gas and electrons, the inert gas and electrons in the atomic cell A being the same as those in the atomic cell B, the atomic cell A and the atomic cell B having the same pressure and the same electron concentration; a pump laser enters the atomic cell A and the atomic cell B respectively, a detection laser is split into two beams of the same light by a beam splitter prism and passes through the atomic cell A and the atomic cell B respectively, and signals of the two cells are collected respectively; an external signal is applied to the X direction and the Y direction by an external coil, a sweep signal within a certain range is realized by continuously adjusting the frequency and phase of the external signal; the detection light signal sigA of the atomic cell A only contains an externally applied external magnetic field signal induced by an external magnetic field, and the detection light signal sigB of the atomic cell B contains the externally applied external magnetic field signal and an atomic precession signal; the light signal sigA of the atomic cell A, the light signal sigB of the atomic cell B, and the externally applied external magnetic field signal sigRef are collected, the collected external magnetic field signal sigRef and the light signal sigA are subjected to the same signal processing, and then multiplied to obtain a noise signal sigNoise in a magnetic resonance phase detection process; the frequency of the externally applied signal is changed within a certain range, the noise signal is added to the external magnetic field signal sigRef, real-time multiplication calculation is performed for different phase signals, and the noise signal consistent with sigNoise is added to the external magnetic field signal sigRef; the phase error of the noise signal sigRef+sigNoise added to the light signal sigA is calculated by PID closed-loop control, the phase of the noise sigNoise added to the external magnetic field signal is fed back and adjusted in real time, and the calculation signal error is suppressed to a fixed value or 0; the adjusted sigRef+sigNoise is multiplied by the light signal sigB to suppress the sigNoise contained in the light signal sigB, and the result of the calculation at this time is the signal of the atomic nucleus spin, i.e. the actual required signal; the output frequency of the detection laser is controlled by PID closed-loop control according to the multiplication calculation result of the light signal sigA and the adjusted sigRef+sigNoise, the phase noise of the detection laser is suppressed, the noise of the detection laser in the magnetic resonance phase signal is suppressed, and the magnetic resonance phase compensation based on external signal compensation is realized.

[0007] Further, the light signal sigA and the light signal sigB contain the same magnetic field noise and the noise introduced by the detection laser, and the external magnetic field signal sigRef is a pure digital signal back sampling generated by a circuit and is considered as a noise-free signal.

[0008] Further, the same signal processing is performed on the collected external magnetic field signal sigRef and the light signal sigA, specifically, low-pass filtering, notch filtering and down-sampling are performed on the collected external magnetic field signal sigRef and the light signal sigA.

[0009] According to another aspect of the present application, a magnetic resonance phase compensation system based on external signal compensation is provided, which uses the magnetic resonance phase compensation method based on external signal compensation as described above to perform magnetic resonance phase compensation.

[0010] Further, the magnetic resonance phase compensation system based on external signal compensation comprises an atom cell A, an atom cell B, a pumping laser, a detection laser, a beam splitter prism, a first photodetector, a second photodetector, an external coil and a signal acquisition system, the atom cell B contains inert gas and isotope nuclei and electrons, the atom cell A contains only inert gas and electrons, the inert gas and electrons in the atom cell A are the same as those in the atom cell B, the pressure and electron concentration of the atom cell A and the atom cell B are the same; the pumping laser output by the pumping laser enters the atom cell A and the atom cell B respectively, the detection laser output by the detection laser is split into two beams of the same light by the beam splitter prism and passes through the atom cell A and the atom cell B respectively, the first photodetector is used to acquire the signal output by the atom cell A, the second photodetector is used to acquire the signal output by the atom cell B, the external coil is used to apply an external signal to the X direction and the Y direction, a sweep signal within a certain range is realized by continuously adjusting the frequency and phase of the external signal, and the signal acquisition system is used to acquire the signals output by the first photodetector and the second photodetector.

[0011] The technical scheme of the application provides a magnetic resonance phase compensation method based on external signal compensation, which acquires light signals sigA and sigB passing through two air chambers, and also acquires an externally applied signal sigRef, multiplies sigA and sigRef to obtain a noise signal synthesis sigNoise, takes the noise signal synthesis sigNoise as an input of a first PID closed-loop control, adds a noise signal consistent with sigNoise to sigRef, suppresses the signal error through closed-loop control, multiplies the adjusted sigRef+sigNoise and sigB to suppress sigNoise contained in sigB, controls the output frequency of the detection laser through a second PID closed-loop control according to the multiplication result of sigA and sigRef+sigNoise, further suppresses the phase noise of the detection laser, completes the noise suppression of the detection laser in the magnetic resonance phase signal, and further realizes the detection precision of the magnetic resonance phase. Therefore, compared with the prior art, the magnetic resonance phase compensation method based on external signal compensation can improve the detection precision of the magnetic resonance phase, effectively solves the technical problem that the single method for forcing the laser to output stable light intensity is relatively single and the implementation means is relatively complicated, and is contrary to the development trend of the increasingly small sensor. BRIEF DESCRIPTION OF DRAWINGS

[0012] The accompanying drawings, which are included to provide a further understanding of the embodiments of the application and constitute a part of the specification, illustrate the embodiments of the application and together with the text description serve to explain the principles of the application. Obviously, the drawings in the following description are only some embodiments of the application, and other drawings can be obtained by those skilled in the art without creative labor.

[0013] Figure 1 A structure diagram of a magnetic resonance phase compensation system based on external signal compensation according to a specific embodiment of the application is shown. DETAILED DESCRIPTION

[0014] It should be noted that the embodiments and features in the application can be combined with each other without conflict. The technical solutions of the embodiments of the application will be described clearly and completely in the following description of the embodiments of the application with reference to the drawings. Obviously, the described embodiments are only some embodiments of the application, not all embodiments. The following description of at least one exemplary embodiment is actually only illustrative, but not as any limitation on the application and its application or use. Based on the embodiments in the application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the application.

[0015] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0016] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the invention. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following figures denote similar items; therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0017] like Figure 1As shown, the specific embodiment according to the present application provides a magnetic resonance phase compensation method based on external signal compensation, which comprises: setting an atomic cell A and an atomic cell B, the atomic cell B containing inert gas and isotope atomic nucleus and electrons, the atomic cell A containing only inert gas and electrons, the inert gas and electrons in the atomic cell A being the same as those in the atomic cell B, the pressure and electron concentration of the atomic cell A and the atomic cell B being the same; a pump laser enters the atomic cell A and the atomic cell B respectively, a detection laser is split into two beams of the same light by a beam splitter prism and passes through the atomic cell A and the atomic cell B respectively, and signals of the two cells are collected respectively; an external signal is applied to the X direction and the Y direction by an external coil, and a sweep signal within a certain range is realized by continuously adjusting the frequency and phase of the external signal; the detection light signal sigA of the atomic cell A only contains an externally applied external magnetic field signal induced by an external magnetic field, and the detection light signal sigB of the atomic cell B contains an externally applied external magnetic field signal and an atomic precession signal; the light signal sigA of the atomic cell A, the light signal sigB of the atomic cell B and the externally applied external magnetic field signal sigRef are collected, the collected external magnetic field signal sigRef and the light signal sigA are subjected to the same signal processing, and then multiplied to obtain a noise signal sigNoise in the magnetic resonance phase detection process; the frequency of the externally applied signal is changed within a certain range, the noise signal is added to the external magnetic field signal sigRef, real-time multiplication calculation is performed for different phase signals, and the noise signal consistent with sigNoise is added to the external magnetic field signal sigRef; the phase error of the noise signal sigRef+sigNoise added and the light signal sigA is calculated by PID closed loop control, the phase of the noise sigNoise added to the external magnetic field signal is fed back and adjusted in real time, so as to suppress the calculation signal error to a fixed value or 0; the adjusted sigRef+sigNoise is multiplied by the light signal sigB to suppress the sigNoise contained in the light signal sigB, and the result of the calculation at this time is the signal of the atomic nucleus spin, i.e. the actual required signal; the result of the multiplication calculation of the light signal sigA and the adjusted sigRef+sigNoise is used to control the output frequency of the detection laser by PID closed loop control, the phase noise of the detection laser is suppressed, the noise suppression of the detection laser in the magnetic resonance phase signal is completed, and the magnetic resonance phase compensation based on external signal compensation is realized.

[0018] With the configuration, the application provides a magnetic resonance phase compensation method based on external signal compensation, which considers that the detection of the magnetic resonance phase is mainly affected by two reasons, one is the output noise of the detection laser itself, and the other is the noise introduced in the atomic pumping process, and aims to improve the accuracy of the magnetic resonance phase detection, and the application provides a magnetic resonance phase noise suppression method based on external signal compensation, by collecting the light signals sigA and sigB passing through the two gas chambers, and collecting the externally applied external signal sigRef, multiplying sigA and sigRef to obtain the noise signal synthesis sigNoise, taking the noise signal synthesis sigNoise as the input of the first PID closed loop control, adding the noise signal consistent with sigNoise to sigRef, and suppressing the calculation signal error through closed loop control; multiplying the adjusted sigRef+sigNoise and sigB to demodulate, so as to suppress the sigNoise contained in sigB; according to the result of multiplying sigA and sigRef+sigNoise, the output frequency of the detection laser is controlled through the second PID closed loop control, the detection laser phase noise is further suppressed, the noise suppression of the detection laser in the magnetic resonance phase signal is completed, and the detection accuracy of the magnetic resonance phase is further realized. Therefore, compared with the prior art, the magnetic resonance phase compensation method based on external signal compensation provided by the application can improve the accuracy of the magnetic resonance phase detection, effectively solve the technical problems that the single forced laser output light intensity stabilization method in the prior art is relatively single, and the implementation means is relatively complicated, which is contrary to the development trend of the increasingly small sensor.

[0019] Further, in the application, the light signal sigA and the light signal sigB contain the same magnetic field noise and the noise introduced by the detection laser, and the external magnetic field signal sigRef is a pure digital signal back sampling generated by a circuit and is considered as a noise-free signal.

[0020] In addition, in the application, the collected external magnetic field signal sigRef and the light signal sigA are subjected to the same signal processing, specifically including low-pass filtering, notch filtering and downsampling of the collected external magnetic field signal sigRef and the light signal sigA.

[0021] According to another aspect of the application, a magnetic resonance phase compensation system based on external signal compensation is provided, which uses the magnetic resonance phase compensation method based on external signal compensation as described above for magnetic resonance phase compensation.

[0022] With the configuration, the magnetic resonance phase compensation system based on external signal compensation is provided, which can improve the accuracy of magnetic resonance phase detection, effectively solve the technical problems that the single forced laser output light intensity stabilizing method is single and the implementation method is complicated, and is contrary to the development trend of small-sized sensors.

[0023] Specifically, as shown in the figure, Figure 1 The magnetic resonance phase compensation system based on external signal compensation comprises an atomic gas chamber A, an atomic gas chamber B, a pumping laser, a detection laser, a beam splitter prism, a first photodetector, a second photodetector, an external coil and a signal acquisition system, the atomic gas chamber B contains inert gas and isotope atomic nuclei and electrons, the atomic gas chamber A contains only inert gas and electrons, the inert gas and the electrons in the atomic gas chamber A are the same as those in the atomic gas chamber B, the pressure and the electron concentration of the atomic gas chamber A and the atomic gas chamber B are the same, the pumping laser output by the pumping laser enters the atomic gas chamber A and the atomic gas chamber B respectively, the detection laser output by the detection laser is split into two beams of the same light by the beam splitter prism and passes through the atomic gas chamber A and the atomic gas chamber B respectively, the first photodetector is used to acquire the signal output by the atomic gas chamber A, the second photodetector is used to acquire the signal output by the atomic gas chamber B, the external coil is used to apply an external signal to the X direction and the Y direction, a sweep signal in a certain range is realized by continuously adjusting the frequency and the phase of the external signal, and the signal acquisition system is used to acquire the signals output by the first photodetector and the second photodetector.

[0024] In order to have a further understanding of the present application, the following Figure 1 The magnetic resonance phase compensation method based on external signal compensation provided by the present application is described in detail.

[0025] As shown in the figure, Figure 1 The influence of the phase noise of the semiconductor laser on the magnetic resonance phase can be realized by two ways of reducing the noise of the semiconductor laser and reducing the influence factor of the noise on the magnetic resonance phase. The detection of the magnetic resonance phase is mainly affected by two reasons, one is the output noise of the detection laser itself, and the other is the noise introduced in the atomic pumping process. The present application provides a magnetic resonance phase noise suppression method based on external signal, which aims to improve the accuracy of magnetic resonance phase detection.

[0026] Generally, an atomic signal sensing system comprises a pumping laser, a detection laser, an atomic gas chamber and an information acquisition system, etc. In the present application, as shown in the figure, Figure 1As shown, compared with the general atomic signal sensing system, a gas chamber is added, the gas chamber B contains inert gas and isotope nuclei and electrons, the gas chamber A only contains inert gas and electrons, the pressure of the gas chamber A and the gas chamber B is the same, and the electron concentration is the same. The inert gas or nitrogen gas is filled in the gas chamber. In the two gas chambers A and B, in order to ensure that there are no other variables except the atomic nuclei for initiating magnetic resonance, the types of inert gas and electrons in the two gas chambers A and B are the same. The isotope atoms in the gas chamber B perform Larmor precession under a strong magnetic field. Under the driving of the pumping laser, the electrons in the gas chamber B are extracted, and the atomic nuclei have the same precession direction. The detection laser is split into two beams of the same light by a beam splitter prism, and the signals of the two gas chambers are collected.

[0027] In the implementation of the scheme, in addition to the existing magnetic field, an external signal is applied to the X direction and the Y direction by an external coil. The frequency and phase of the signal are controlled by external hardware. The frequency and phase of the external signal are continuously adjusted to realize a sweep signal within a certain range.

[0028] In the two gas chambers,

[0029] The detection light signal sigA passing through the gas chamber A only contains the externally applied external signal induced by the external magnetic field,

[0030] The detection light signal sigB passing through the gas chamber B contains the externally applied external magnetic field signal and the atomic precession signal.

[0031] In the signal collection process, in addition to collecting the light signals sigA and sigB passing through the two gas chambers, the externally applied external signal sigRef is also collected. The sigA and sigB contain the same magnetic field noise and noise introduced by the detection laser, and the sigRef is a pure digital signal collected by a circuit and is considered as a noise-free signal.

[0032] The signal processing and implementation process is as follows:

[0033] 1. In the signal processing process, the collected sigRef and sigA signals are first processed in the same way (the signal processing generally refers to the data processing process such as low-pass filtering, wave trapping, and downsampling. The processing process is different according to different quantum sensor devices and processing algorithms), and then multiplied. Since the sigA contains noise signals introduced by the laser and the externally applied magnetic field, and the sigRef is a pure digital signal, the result of the multiplication of sigA and sigRef is the noise signal sigNoise in the entire magnetic resonance phase detection process. The purpose of multiplication is to calculate the actual signal phase, and the working principle of the phase-locked amplifier. This step is common.

[0034] 2, change the frequency of the external applied signal within a certain range, so as to add noise signal to sigRef, real-time multiplication calculation is carried out for different phase signals (i.e. multiplication calculation of sigA and sigRef is carried out in real time), so as to add noise signal close to sigNoise to sigRef. Through PID closed loop control, the phase error of the noise signal sigRef+sigNoise and sigA is calculated, the reference signal phase is fed back and adjusted in real time, so as to suppress the calculation signal error to a fixed value or close to 0. The reference signal phase refers to the noise signal doped in sigRef, which is represented by sigNoise in the description. The patent specification contains two PID closed loops, the first PID closed loop adjusts the phase of the noise doped in the reference signal sigRef, i.e. sigNoise, and the subsequent PID closed loop structure adjusts the phase noise of the detected laser in step 4. In the adjustment process, the PID closed loop structure in step 2 adjusts the noise signal doped in the reference signal sigRef, which is represented by sigNoise in the text. In the process of adjusting the frequency, there will be a certain error in the actual calculation result, which cannot be guaranteed to be 0. When the calculation result is near a constant value, it is considered that the adjustment is completed, and the constant value is not necessarily the preset fixed value.

[0035] 3, multiply sigRef+sigNoise after adjustment with sigB to demodulate, so as to suppress sigNoise contained in sigB, and the result after calculation is the signal of nuclear spin, i.e. the actual required signal.

[0036] 4, according to the multiplication calculation result of sigA and sigRef+sigNoise, the output frequency of the detected laser is controlled through PID closed loop control, the phase noise of the detected laser is further suppressed, the noise suppression of the detected laser in the magnetic resonance phase signal is completed, and the detection accuracy of the magnetic resonance phase is further realized.

[0037] In summary, the application provides a magnetic resonance phase compensation method based on external signal compensation, which acquires light signals sigA and sigB passing through two air chambers, and also acquires an externally applied external signal sigRef, multiplies sigA and sigRef to obtain a noise signal synthesis sigNoise, takes the noise signal synthesis sigNoise as the input of a first PID closed-loop control, adds a noise signal consistent with sigNoise to sigRef, and suppresses the calculation signal error through closed-loop control; multiplies the adjusted sigRef+sigNoise and sigB to demodulate, thereby suppressing the sigNoise contained in sigB; according to the result of multiplying sigA and sigRef+sigNoise, the output frequency of the detection laser is controlled through a second PID closed-loop control, further suppressing the detection laser phase noise, completing the noise suppression of the detection laser in the magnetic resonance phase signal, and further realizing the detection accuracy of the magnetic resonance phase. Therefore, compared with the prior art, the magnetic resonance phase compensation method based on external signal compensation provided by the application can improve the accuracy of magnetic resonance phase detection, effectively solve the technical problems of the prior art that the single forced laser output light intensity stabilization method is relatively single, and the implementation means is relatively complicated, which is contrary to the development trend of the increasingly small sensor.

[0038] For the sake of description, spatial relative terms, such as "above", "upper", "top", "bottom", and the like, can be used herein for ease of description to describe the spatial relationship of one device or feature to another device or feature as shown in the drawings. It should be understood that the spatial relative terms are intended to include different orientations of the device in use or operation in addition to the orientation of the device described in the drawings. For example, if the device in the drawing is inverted, the device described as "above" or "above" the other device or structure will be positioned "below" or "below" the other device or structure. Thus, the exemplary term "above" can include both "above" and "below" orientations. The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein are interpreted accordingly.

[0039] In addition, it should be noted that the use of "first", "second", and the like to define parts is only for the convenience of distinguishing the corresponding parts, and the above words have no special meaning unless otherwise stated, and therefore cannot be understood as limiting the scope of protection of the application.

[0040] The above merely provides the preferred embodiments of the present application, and is not used to limit the present application. For those skilled in the art, the present application can have various modifications and changes. Any modifications, equivalent replacements, improvements, etc. made within the principles and technical scope of the present application shall fall into the scope of the present application.

Claims

1. A magnetic resonance phase compensation method based on external signal compensation, characterized in that, The magnetic resonance phase compensation method based on external signal compensation includes: Atomic gas chambers A and B are provided. Atomic gas chamber B contains inert gas, isotopic atomic nuclei, and electrons. Atomic gas chamber A contains only inert gas and electrons. The inert gas and electrons in atomic gas chamber A are the same as those in atomic gas chamber B. Atomic gas chamber A and atomic gas chamber B have the same pressure and the same electron concentration. The pumped laser enters atomic gas chamber A and atomic gas chamber B respectively. The detection laser is split into two identical beams by a beam splitter and passes through atomic gas chamber A and atomic gas chamber B respectively, and the signals of the two gas chambers are collected respectively. An external signal is applied to both the X and Y directions by an external coil. A frequency sweep signal within a certain range is achieved by continuously adjusting the frequency and phase of the external signal. The detection light signal sigA passing through atomic gas chamber A contains only the actively applied external magnetic field signal sensed by the external magnetic field, while the detection light signal sigB passing through gas chamber B contains both the actively applied external magnetic field signal and the atomic precession signal. The optical signal sigA from atomic gas cell A, the optical signal sigB from atomic gas cell B, and the actively applied external magnetic field signal sigRef are collected. The collected external magnetic field signal sigRef and optical signal sigA are subjected to the same signal processing, and then multiplied to obtain the comprehensive noise signal sigNoise in the magnetic resonance phase detection process. The frequency of the externally applied signal is changed within a certain range to introduce noise into the external magnetic field signal sigRef. Real-time multiplication is performed for different phase signals to add noise consistent with sigNoise to the external magnetic field signal sigRef. Through PID closed-loop control, the phase error between the noise signal sigRef+sigNoise and the optical signal sigA is calculated, and the phase of the noise sigNoise in the external magnetic field signal is fed back and adjusted in real time to suppress the calculated signal error to a fixed value or 0. The adjusted sigRef+sigNoise is multiplied and demodulated with the optical signal sigB to suppress the sigNoise contained in the optical signal sigB. The result after the calculation is the signal of the atomic nucleus spin, which is the signal actually needed. Based on the result of multiplying the optical signal sigA and the adjusted sigRef+sigNoise, the output frequency of the detection laser is controlled by PID closed-loop control to suppress the phase noise of the detection laser, thereby achieving noise suppression of the detection laser in the magnetic resonance phase signal and realizing magnetic resonance phase compensation based on external signal compensation.

2. The magnetic resonance phase compensation method based on external signal compensation according to claim 1, characterized in that, The optical signals sigA and sigB contain the same magnetic field noise and noise introduced by the detection laser. The external magnetic field signal sigRef is a pure digital signal sampled from the circuit and is considered to be a noise-free signal.

3. The magnetic resonance phase compensation method based on external signal compensation according to claim 2, characterized in that, The same signal processing is applied to the acquired external magnetic field signal sigRef and optical signal sigA, specifically including low-pass filtering, notch filtering, and downsampling.

4. A magnetic resonance phase compensation system based on external signal compensation, characterized in that, The magnetic resonance phase compensation system based on external signal compensation uses the magnetic resonance phase compensation method based on external signal compensation as described in claims 1 to 3 to perform magnetic resonance phase compensation.

5. The magnetic resonance phase compensation system based on external signal compensation according to claim 4, characterized in that, The magnetic resonance phase compensation system based on external signal compensation includes atomic gas chamber A, atomic gas chamber B, a pump laser, a detection laser, a beam splitter, a first photodetector, a second photodetector, an external coil, and a signal acquisition system. Atomic gas chamber B contains inert gas and isotopic atomic nuclei and electrons, while atomic gas chamber A contains only inert gas and electrons. The inert gas and electrons in atomic gas chamber A are the same as those in atomic gas chamber B. Atomic gas chambers A and B have the same pressure and electron concentration. The pump laser output from the pump laser enters... The detection laser output from the detection laser is split into two identical beams by the beam splitter and passes through atomic gas chambers A and B respectively. The first photodetector is used to collect the signal output from atomic gas chamber A, and the second photodetector is used to collect the signal output from atomic gas chamber B. The external coil is used to apply an external signal in both the X and Y directions. By continuously adjusting the frequency and phase of the external signal, a frequency sweep signal within a certain range is achieved. The signal acquisition system is used to collect the signals output by the first photodetector and the second photodetector.

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