An adaptive calibration high frequency test method and system

Abstract

The application discloses a kind of self-adapting calibration high-frequency test method and system.The method relates to the technical field of measuring magnetic variable, including the following steps: signal interference quantization;Signal interference optimization;Uniformity influence quantization and magnetic field uniformity optimization.The application obtains the quantization result of signal interference by the signal interference parameter, and judges whether signal interference optimization is carried out, if yes, then after signal interference optimization is qualified, magnetic field uniformity test is carried out, otherwise, directly magnetic field uniformity test is carried out and obtains uniformity influence parameter, obtains magnetic field uniformity influence coefficient in combination with the uniformity influence parameter obtained, and judges whether magnetic field uniformity optimization is carried out, if yes, then after magnetic field uniformity optimization is qualified, high-frequency test is carried out, otherwise, directly high-frequency test is carried out, and then the high-frequency test accuracy is improved, the problem that the high-frequency test accuracy is low due to sample position offset in prior art is solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of measuring magnetic variables, in particular to a high-frequency test method and system with adaptive calibration. BACKGROUND

[0002] In the field of high-frequency testing, especially in complex test scenarios involving low or high temperatures, first, during the high-frequency test preparation phase, the sample rod is installed on the moving slide table of the high-frequency test system, at this time a temporary or preliminary fixing method is adopted to leave space for subsequent accurate adjustment. The sample rod and the sample (such as a thin film, a block, etc.) carried by it are scanned using an inductance sensor array. The inductance sensor can non-contact detect the geometric characteristics of the sample rod or the sample. Based on the geometric characteristic information of the sample rod or the sample, the accurate coordinates of the sample center point and the normal direction of the sample surface and other key attitude parameters can be calculated, and their positions relative to the reference coordinate system of the high-frequency test are determined. This step establishes the initial reference geometric information of the sample. Next, the entire high-frequency test environment (including the sample and the slide table) is placed in a low or high temperature environment to simulate actual working conditions. Under this condition, a high-precision magnetic field measuring device such as a Hall probe array is used to accurately measure the magnetic field strength and direction of each point in space, and a three-dimensional space model of the magnetic field uniform area is established. This model not only indicates the core area with the most uniform magnetic field strength, but also determines the center position, effective size (length, width and height) of the most uniform magnetic field area, and the boundary where the magnetic field uniformity meets the standard. Then, the initial reference geometric information of the sample obtained before is matched and calculated with the three-dimensional model of the magnetic field uniform area. The core goal is to accurately place the sensitive area (such as the resonance area) of the sample at the geometric center of the magnetic field uniform area. The sample is moved to the target magnetic flux position by motor driving, including the translation distance of the sample in X, Y and Z three axial directions and the rotation angle around the three axes. The moving slide table will be adjusted according to the calculated adjustment amount to position the sample to the center position of the magnetic field uniform area.

[0003] For example, the ferromagnetic resonance testing device and method disclosed in Chinese patent CN106950518A includes a base and a sample loading assembly arranged on the base. The sample loading assembly includes a translation assembly, a first rotation assembly and a sample platform for carrying a sample to be tested. The first rotation assembly is connected with the sample platform and drives the sample platform to rotate within any angle of the first plane where the sample platform is located. The translation assembly is connected with the sample platform and is used to move the sample platform to separate the sample to be tested and the planar waveguide.

[0004] For example, the Chinese invention patent with publication number CN115421083A discloses a magnetic field testing device and method based on high-frequency magnetic sensor, which includes: a rotating seat that can rotate around its center; a rotating rod with one end set on the center; a sample seat set on the other end of the rotating rod for setting GSG sheet and GSG binding wire, the GSG binding wire is set on the GSG sheet and connected with the sensor to be tested; a biasing device connected with the other end of the GSG binding wire; a high-frequency source for providing high-frequency signal and connected with the biasing device; a lock-in amplifier connected with the high-frequency source and the biasing device respectively; two electromagnets symmetrically set on both sides of the rotating shaft of the rotating rod.

[0005] The above technology at least has the following technical problems:

[0006] In low-temperature or high-temperature high-frequency testing, the sample needs to be placed in a precisely controlled magnetic field and temperature environment for performance detection. The existing sample rod is usually fixed by flange and O-ring near the high-frequency testing equipment, lacking rigid support. In low-temperature / high-temperature environment, due to thermal expansion and contraction or mechanical vibration, the sample rod is easy to tilt, causing the sample to deviate from the uniform area of the magnetic field; if the sample is not in the uniform area of the magnetic field, the actual magnetic flux measured is not consistent with the standard value, and after long-term use, residual magnetic field or coil defects may occur, causing the magnetic field distribution to deviate from the ideal state, further exacerbating the non-uniformity of the magnetic field, and there is a problem of low accuracy of high-frequency testing caused by sample position deviation. SUMMARY

[0007] In order to solve the problem of low accuracy of high-frequency testing caused by sample position deviation in the prior art, the embodiments of the present application provide a self-adaptive calibration high-frequency testing method and system. The technical solution is as follows:

[0008] In one aspect, a self-adaptive calibration high-frequency test method is provided, comprising: before high-frequency test, monitoring the magnetic field intensity of a moving slide table by using a three-dimensional magnetic sensitive Hall sensor and obtaining corresponding signal interference parameters, and quantifying the degree of ferromagnetic resonance signal interference according to the obtained signal interference parameters; judging whether to perform signal interference optimization according to the quantification result of the signal interference, if yes, then performing magnetic field uniformity test after signal interference optimization is qualified, otherwise, directly performing magnetic field uniformity test and obtaining uniformity influence parameters; the signal interference optimization means performing temperature drift compensation optimization to reduce the measurement error of the ferromagnetic resonance signal caused by temperature interference, and performing coil current compensation optimization to reduce the measurement error of the ferromagnetic resonance signal caused by unstable coil current; obtaining a magnetic field uniformity influence coefficient to represent the influence degree of the magnetic field non-uniformity on the ferromagnetic resonance signal measurement by combining the obtained uniformity influence parameters; judging whether to perform magnetic field uniformity optimization according to the magnetic field uniformity influence coefficient, if yes, then performing high-frequency test after the magnetic field uniformity optimization is qualified, otherwise, directly performing high-frequency test; the magnetic field uniformity optimization means performing magnetic field pre-setting to determine the direction of the magnetic field change, and then performing sample displacement amount optimization to improve the adaptation degree of the sample and the magnetic field magnetic flux distribution.

[0009] In another aspect, a self-adaptive calibration high-frequency test system is provided, comprising: a signal interference parameter quantification module, a signal interference optimization module, a uniformity influence parameter quantification module and a magnetic field uniformity optimization module; the signal interference parameter quantification module is used to monitor the magnetic field intensity of a moving slide table by using a three-dimensional magnetic sensitive Hall sensor and obtain corresponding signal interference parameters before high-frequency test; the signal interference optimization module is used to judge whether to perform signal interference optimization according to the quantification result of the signal interference, if yes, then perform magnetic field uniformity test after signal interference optimization is qualified, otherwise, directly perform magnetic field uniformity test and obtain uniformity influence parameters; the uniformity influence parameter quantification module is used to obtain a magnetic field uniformity influence coefficient to represent the influence degree of the magnetic field non-uniformity on the ferromagnetic resonance signal measurement by combining the obtained uniformity influence parameters; the magnetic field uniformity optimization module is used to judge whether to perform magnetic field uniformity optimization according to the magnetic field uniformity influence coefficient, if yes, then perform high-frequency test after the magnetic field uniformity optimization is qualified, otherwise, directly perform high-frequency test.

[0010] The technical scheme provided by the embodiments of the present application has at least the following beneficial effects:

[0011] 1、Through the three-dimensional magnetic sensitive Hall sensor, the magnetic field intensity of the moving slide table is monitored and the corresponding signal interference parameters are obtained, and the ferromagnetic resonance signal interference coefficient is obtained according to the obtained signal interference parameters, the ferromagnetic resonance signal interference coefficient can quantify the degree of interference of the ferromagnetic resonance signal, whether to perform signal interference optimization to improve the reliability of the ferromagnetic resonance signal monitoring is judged according to the ferromagnetic resonance signal interference coefficient, if yes, temperature drift compensation optimization is performed to reduce the measurement error of the ferromagnetic resonance signal caused by temperature interference, and coil current compensation optimization is performed to reduce the measurement error of the ferromagnetic resonance signal caused by unstable coil current, and after the signal interference optimization, the magnetic field uniformity test is performed, otherwise, the magnetic field uniformity test is directly performed and the uniformity influence parameter is obtained, the magnetic field uniformity influence coefficient is obtained combined with the obtained uniformity influence parameter, and whether to perform magnetic field uniformity optimization to improve the magnetic field uniformity is judged, if yes, the magnetic field pre-setting is performed to determine the direction of the magnetic field change, then the sample displacement optimization is performed to improve the adaptability of the sample and the magnetic field magnetic flux distribution, and after the optimization, the high frequency test is performed, thereby realizing the whole link precision improvement from the ferromagnetic resonance signal to the high frequency test, and the high frequency test accuracy is improved.

[0012] 2、Through the ferromagnetic resonance signal interference coefficient, whether to perform signal interference optimization to solve the problem of interference of the ferromagnetic resonance signal is judged, if yes, whether to perform temperature drift compensation optimization according to the average temperature of the sample is judged to reduce the measurement error of the ferromagnetic resonance signal caused by temperature interference, thereby ensuring the stability of the ferromagnetic resonance signal frequency characteristics, and whether to perform coil current compensation optimization according to the average magnetic induction intensity is judged to reduce the measurement error of the ferromagnetic resonance signal caused by unstable coil current, thereby providing standardized input for the high frequency test, and the distortion of the ferromagnetic resonance signal caused by the magnetic field intensity transient is reduced, and the stability of the ferromagnetic resonance signal measurement is improved.

[0013] 3、Through the magnetic field uniformity influence coefficient, whether to perform magnetic field uniformity optimization to solve the problem of influence of the magnetic field uniformity is judged, if yes, the moving direction of the sample in the magnetic field pre-setting process is determined according to the comparison of the magnetic field intensity of the current position of the sample in the magnetic field pre-setting process and the magnetic field intensity of the starting position of the sample to quantify the magnetic field gradient distribution and determine the optimal magnetic field uniformity direction, after determining the direction of the magnetic field change, whether to perform sample displacement optimization is judged according to the magnetic field change gradient to improve the adaptability of the sample and the magnetic field magnetic flux distribution, and then the motor drives the sample to the target position to realize the real-time matching of the sample position and the magnetic field distribution, thereby realizing the accuracy improvement from the magnetic field uniformity optimization to the high frequency test method. BRIEF DESCRIPTION OF DRAWINGS

[0014] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced as follows.

[0015] Figure 1 A flow chart of a self-adaptive calibration high-frequency test method provided for an embodiment of the present application;

[0016] Figure 2 A structure diagram of an FMR sample rod provided for an embodiment of the present application;

[0017] Figure 3 A structure and main component diagram of a ferromagnetic resonance rotating module provided for an embodiment of the present application;

[0018] Figure 4 A test software main interface diagram of a self-adaptive calibration high-frequency test method provided for an embodiment of the present application;

[0019] Figure 5 A pop-up window corresponding to a Sequence command of a self-adaptive calibration high-frequency test method provided for an embodiment of the present application;

[0020] Figure 6 A flow chart of temperature drift compensation optimization of a self-adaptive calibration high-frequency test method provided for an embodiment of the present application;

[0021] Figure 7 A flow chart of coil current compensation optimization of a self-adaptive calibration high-frequency test method provided for an embodiment of the present application;

[0022] Figure 8 A schematic diagram of sample rod installation into a ColdTUBE low-temperature superconducting magnet system provided for an embodiment of the present application;

[0023] Figure 9 A structure schematic diagram of a self-adaptive calibration high-frequency test system provided for an embodiment of the present application;

[0024] Figure 10 An illustration of ferromagnetic resonance test principle of a self-adaptive calibration high-frequency test method provided for an embodiment of the present application;

[0025] Figure 11 A test software status bar interface and communication address setting interface diagram of a self-adaptive calibration high-frequency test method provided for an embodiment of the present application;

[0026] Figure 12 A high-temperature-temperature test diagram of a self-adaptive calibration high-frequency test method provided for an embodiment of the present application;

[0027] Fig. 1, coil connector (SMA-F); 2, dial; 3, coplanar waveguide; 4, Helmholtz coil; 5, radio frequency connector (2.92 / SMA-F); 6, direct current measurement connector (Lemo-14Pin); 7, heat radiation screen; 8, coil connector (BNC-F); 9, direct current measurement connector (aviation plug-19Pin); 11, temperature control connector (aviation plug-10Pin); 12, mounting flange (KF40 / KF50); 13, modulation coil; 14, direct current electrode; 15, coplanar waveguide; 16, temperature control module. DETAILED DESCRIPTION

[0028] To make the technical problems, technical solutions and advantages to be solved by the present application clearer, specific embodiments will be described in detail below with reference to the drawings.

[0029] As shown in the flow chart of the high-frequency test method provided by the embodiment of the present application, the processing flow of the method can include the following steps: Figure 1 Before high-frequency test, the magnetic field intensity of the mobile slide table is monitored by using a three-dimensional magnetic sensitive Hall sensor, and the corresponding signal interference parameters are obtained. The three-dimensional magnetic sensitive Hall sensor is a cubic sensor provided with a plurality of Hall elements, configured to measure the three-dimensional air gap magnetic field, and to quantify the degree of interference of the ferromagnetic resonance signal according to the obtained signal interference parameters; according to the quantization result of the signal interference (i.e. the ferromagnetic resonance signal interference coefficient), it is determined whether to perform signal interference optimization. If yes, after the signal interference optimization is qualified, the magnetic field uniformity test is performed, otherwise, the magnetic field uniformity test is directly performed and the uniformity influence parameters are obtained. The signal interference optimization means to perform temperature drift compensation optimization to reduce the measurement error of the ferromagnetic resonance signal caused by temperature interference, and to perform coil current compensation optimization to reduce the measurement error of the ferromagnetic resonance signal caused by unstable coil current; the magnetic field uniformity influence coefficient is obtained by combining the obtained uniformity influence parameters to represent the influence degree of the magnetic field non-uniformity on the ferromagnetic resonance signal measurement; according to the magnetic field uniformity influence coefficient, it is determined whether to perform magnetic field uniformity optimization. If yes, after the magnetic field uniformity optimization is qualified, the high-frequency test is performed, otherwise, the high-frequency test is directly performed. The magnetic field uniformity optimization means to perform magnetic field pre-setting to determine the direction of magnetic field change, and then to perform sample displacement optimization to improve the adaptation degree of the sample and the magnetic flux distribution of the magnetic field.

[0030]

[0031] ​It should be noted that the signal interference optimization qualified refers to that the ferromagnetic resonance signal interference coefficient is less than or equal to the ferromagnetic resonance signal interference set value, wherein if the signal interference optimization is performed, the corresponding ferromagnetic resonance signal interference coefficient is the corresponding data obtained after the signal interference optimization; the magnetic field uniformity optimization qualified refers to that the magnetic field uniformity influence coefficient is less than or equal to the magnetic field uniformity influence set value, wherein if the magnetic field uniformity optimization is performed, the corresponding magnetic field uniformity influence coefficient is the corresponding data obtained after the magnetic field uniformity optimization. The ferromagnetic resonance, simply understood, is to make the spin in the electron precession resonance, and a high-frequency microwave magnetic field or an electric field can excite the disturbance, and the temperature also affects the disturbance condition of the spin.

[0032] In the embodiment, the application takes "ferromagnetic resonance signal interference elimination-magnetic field uniformity optimization-high frequency test" as the core logic. Through the core logic process, the interference elimination from the source of the ferromagnetic resonance signal to the precise uniformity optimization of the magnetic field environment is realized, and finally the high-quality ferromagnetic resonance signal input is obtained in the high-frequency test link, which significantly improves the measurement accuracy and stability of the ferromagnetic resonance signal and reduces the measurement error caused by the ferromagnetic resonance signal interference.

[0033] It should be noted that the test sample rod contains two types, which are a low-temperature sample rod and a room temperature rotating test module. Among them, the low-temperature sample rod can be compatible with most third-party low-temperature superconducting magnet platforms, and is suitable for ferromagnetic resonance measurement in the temperature range of 1.6K-400K and the magnetic field range of 0-14T; and the room temperature rotating test module can be compatible with most electromagnets platforms, and is suitable for ferromagnetic resonance measurement in the magnetic field range of 0-2T at room temperature, and the module supports sample rotation function.

[0034] In actual application, the FMR sample rod is quite particular in material selection in design, especially the microwave test channel, which is entirely processed and manufactured by non-magnetic materials. The purpose of this is to minimize the influence of noise and background signal on the measurement results and ensure the accuracy of the test. The core measurement component of the sample rod is a straight-through coplanar waveguide. During testing, the sample can be directly placed on the surface of the coplanar waveguide for related measurement. The FMR sample rod mainly has two structures, one of which is a structure with the magnetic field parallel to the sample plane, such as Figure 2As shown in the structural diagram of the FMR sample rod provided by the embodiment of the application, all the microwave test channels are processed using non-magnetic materials to avoid the influence of noise and background signals to the greatest extent. The radio frequency channel of the FMR sample rod is composed of a coaxial cable, a coaxial adapter and a coplanar waveguide. The core measuring component is a straight-through coplanar waveguide, and the sample is directly placed on the surface of the coplanar waveguide for testing. Another structure is that the magnetic field is perpendicular to the sample plane. Moreover, all the sample rods can be matched with a rotating motor. With the help of the rotating motor, the sample rod can rotate along the Z axis, so as to realize the ferromagnetic resonance test under the condition of the change of the magnetic field angle.

[0035] It should be noted that when designing an adaptive calibration high-frequency test system, a high-frequency test database specially storing core configuration information is first created. The database stores various setting values necessary for system operation, such as key data such as sample rod inclination angle setting value, microwave frequency setting value, temperature change amount setting value and ferromagnetic resonance signal interference setting value. The initial setting of these setting values is not randomly specified, but is calculated by summation average method based on a large amount of measured data accumulated in the high-frequency test database. The purpose of this is to make the initial setting more objective and more reflective of the general situation. Of course, considering the complex and changeable actual application environment and the new problems that may occur in the system debugging process, these values in the high-frequency test database are not fixed. The technical personnel can manually set, adjust or fine-tune them at any time according to the specific performance of the system in actual testing, to ensure that the system can be continuously optimized to achieve the best working state.

[0036] It should be noted that, as Figure 3As shown, the structure and main components of the ferromagnetic resonance rotating module provided by the embodiment of the application are shown, the coil connector (SMA-F) 1 is used to connect an external circuit or instrument to supply power to the Helmholtz coil 4, so that the Helmholtz coil 4 generates a uniform magnetic field; the dial 2 is connected with the stepper motor, and is used to indicate the angle of the CPW 3; when the stepper motor rotates, it drives the CPW 3 to rotate, and the dial 2 displays the current rotation angle; the CPW (Coplanar Waveguide, CPW) 3 is the core part of the ferromagnetic resonance experiment, and the sample is placed on its surface; the design of the CPW allows the microwave signal to propagate along its length and interact with the sample; the Helmholtz coil 4 is a modulation coil that generates an alternating magnetic field, which is necessary for exciting the ferromagnetic resonance of the sample, and the coil connector (SMA-F) 1 supplies power to it; the RF connector (2.92 / SMA-F) 5 is used to connect the RF signal source or spectrum analyzer to send and receive microwave signals, which are used to excite and detect the ferromagnetic resonance of the sample; the DC measurement connector (Lemo-14Pin) 6 is used to connect the DC power supply or other measuring instruments to provide additional power or perform other types of measurements. The ferromagnetic resonance rotating module integrates a stepper motor to control the angle of the CPW, so that the sample can rotate relative to the magnetic field at 0°-360°. The core measurement component is a straight-through CPW 3, and the sample is directly placed on the surface of the CPW for testing. After determining the direction of the increasing magnetic field, a target position (a movement instruction based on time or speed) is set, the target position (or target movement amount) is used as the set point of the PID (Proportional-Integral-Derivative controller, PID) controller, and the actual position (or actual movement amount) of the motor is used as the process variable. According to the size and change rate of the error, the PID controller calculates the corresponding control output (usually a voltage or current signal). The output signal of the PID controller is sent to the motor driver to drive the motor to move the sample module by the calculated accurate amount, so that it advances in the direction of the increasing magnetic field.

[0037] It should be noted that, as Figure 4The figure shows the main interface of the test software for a high-frequency test method with adaptive calibration provided by an embodiment of the present invention. In this integrated interface, the top area displays the title "Multi-Function Measurement System", indicating that this is a software interface for multiple measurements; the left area has a series of blue buttons, each with a corresponding icon next to it, representing different measurement functions or operation options. For example, some buttons may be used to start, stop, or save measurements. There is a large blank area in the middle area, which is a window for displaying measurement results or other related information. Above this area are some smaller text boxes for entering parameters or setting measurement conditions. When the test software for the high-frequency test method is running, the blank area in the middle area will display cavity status information such as magnetic field, temperature, and angle, and free programming testing can be achieved by stacking command lines.

[0038] like Figure 5 As shown, a pop-up window corresponding to the Sequence command of a high-frequency test method for adaptive calibration provided by an embodiment of the present invention is shown. The Sequence command button is used to control the execution of the current test Sequence. The window that pops up when each button is clicked is shown, and the functions of each button are: Start: Start running the test in the order of commands in the Sequence, and you can choose to start the run at the starting position or the highlighted position; Save: Save the current Sequence, and save the currently edited Sequence as a text file locally on the computer; Open: Open a local text file as a Sequence; Pause: Pause the Sequence, and do not continue to execute the next line of commands after executing the current line of commands; After clicking Pause, the button will change to Continue, and clicking it again will continue to execute the Sequence; Clear: Clear all commands in the current Sequence box; Plot: Draw images in real time during the test. Clicking it will pop up the Curve-Plotting dialog box, and you can select the XY axis of the image to be drawn. Three images can be drawn at the same time.

[0039] It is further explained that the signal interference parameters specifically include: sample rod inclination angle, microwave frequency and temperature change amount. According to the obtained signal interference parameters, the degree of interference of the ferromagnetic resonance signal is quantified, specifically: the signal interference setting value and the signal interference correction amount are obtained from the constructed high-frequency test database, the signal interference parameters are corrected with the signal interference correction amount and the proportion analysis result of the signal interference setting value, to obtain the ferromagnetic resonance signal interference coefficient, wherein the proportion analysis represents the division operation; the signal interference setting value specifically includes the sample rod inclination angle setting value, the microwave frequency setting value and the temperature change amount setting value, and the signal interference correction amount specifically includes the sample rod inclination angle correction amount, the microwave frequency correction amount and the temperature change amount correction amount.

[0040] Wherein, the ferromagnetic resonance signal interference coefficient is the degree of interference of the ferromagnetic resonance signal reflected by the signal interference parameters and the signal interference setting value together, that is, the quantification result of the signal interference.

[0041] The specific limit expression of the ferromagnetic resonance signal interference coefficient is:

[0042] ;

[0043] ;

[0044] In the formula, D represents the ferromagnetic resonance signal interference coefficient. Q1 represents the sample rod inclination angle correction quantity obtained from the high-frequency test database, A represents the angle by which the sample rod deviates from its preset vertical and horizontal position measured by the micro-electro-mechanical system gyroscope, A1 represents the sample rod inclination angle setting value obtained from the high-frequency test database, and the sample rod inclination angle will produce a non-zero offset due to environmental factors such as vibration, so the sample rod inclination angle setting value obtained from the high-frequency test database is not 0, so as to adapt to the sample rod inclination angle change caused by physical interference in the actual test scene. The greater the sample rod inclination angle, the greater the deviation of the sample from the magnetic field uniform region, the magnetic field gradient effect is triggered, and the ferromagnetic resonance signal interference coefficient is increased. Q2 represents the microwave frequency correction quantity obtained from the high-frequency test database, B represents the oscillation frequency of the electromagnetic wave in the microwave frequency range measured by the spectrum analyzer, and B1 represents the microwave frequency setting value obtained from the high-frequency test database. The greater the deviation between the microwave frequency and the ferromagnetic resonance frequency, the more obvious the signal strength attenuation, the signal phase shift, and the ferromagnetic resonance signal interference coefficient is increased. Q3 represents the temperature change quantity correction quantity obtained from the high-frequency test database, C represents the initial temperature and the final temperature of the sample in the wide-temperature-zone test time measured by the thermocouple, and the absolute value of the final temperature and the initial temperature difference is recorded as the temperature change quantity to reflect the temperature change of the sample in the wide-temperature-zone test time, and C1 represents the temperature change quantity setting value obtained from the high-frequency test database. The greater the temperature change quantity, the greater the change in the magnetic field uniformity, the easier to excite spin waves, the more serious the ferromagnetic resonance signal distortion, and the greater the ferromagnetic resonance signal interference coefficient.

[0045] It should be noted that the high-frequency test database stores three types of correction quantities corresponding to the signal interference parameters, namely the sample rod inclination angle correction quantity, the microwave frequency correction quantity, and the temperature change quantity correction quantity, and the numerical range is generally between 0 and 1, and the sum of the three types of correction quantities is always 1. There is a pre-set mapping relationship between the signal interference parameters and the corresponding three types of correction quantities, which can be a one-to-one correspondence or a many-to-one correspondence. For example, in actual application, the real-time signal interference parameters can be substituted into the mapping relationship to quickly obtain the corresponding correction quantity.

[0046] Meanwhile, the parameters involved in the ferromagnetic resonance signal interference coefficient have correlations, which are as follows: the higher the microwave frequency, the stronger the microwave absorption, which causes the temperature of the sample to rise, and the higher the temperature change quantity; the higher the temperature change quantity, the magnetic properties of the sample change, which directly leads to the shift of the ferromagnetic resonance peak position and the change of the sample shape, and the greater the sample rod inclination angle; the greater the sample rod inclination angle, the higher the coupling efficiency, which leads to stronger microwave heating, and the higher the microwave frequency, the greater the temperature change.

[0047] In the embodiment, by understanding the correlation between the sample rod inclination angle, the microwave frequency and the temperature change amount, the signal interference parameters are monitored in real time, the sample temperature drift caused by coupling is avoided, and a cross-domain regulation framework of mechanical posture-electromagnetic parameters-thermal effect is constructed; by understanding the positive and negative correlation between the sample rod inclination angle, the microwave frequency, the temperature change amount and the ferromagnetic resonance signal interference coefficient, a "cause-response" regulation link of the ferromagnetic resonance signal interference is constructed, and the measurement accuracy of the ferromagnetic resonance signal is improved.

[0048] Further, the specific judgment steps of judging whether to perform signal interference optimization are as follows: obtaining the ferromagnetic resonance signal interference set value from the constructed high-frequency test database; if the ferromagnetic resonance signal interference coefficient is less than or equal to the ferromagnetic resonance signal interference set value, signal interference optimization is not performed; if the ferromagnetic resonance signal interference coefficient is greater than the ferromagnetic resonance signal interference set value, whether to perform temperature drift compensation optimization is judged according to the sample average temperature, if yes, whether to perform coil current compensation optimization is judged after the temperature drift compensation optimization is performed, otherwise, whether to perform coil current compensation optimization is directly judged; the sample average temperature represents the average value of the temperature of the sample at the wide temperature range test time point.

[0049] It should be noted that, as shown in Figure 6 the flow chart of the temperature drift compensation optimization of the self-adaptive calibration high-frequency test method provided by the embodiment of the application, the specific logic is as follows: comparing the sample average temperature with the preset sample temperature maximum value, if the sample average temperature is greater than the preset sample temperature maximum value, the harmonic average result of the signal interference correction amount and the temperature correction amount is temperature effective value processed to obtain the temperature compensation amount, otherwise, whether the sample average temperature is within the preset sample temperature standard interval is judged, if the sample average temperature is within the preset sample temperature standard interval, temperature drift compensation optimization is not performed, otherwise, the harmonic average result of the signal interference correction amount and the temperature influence amount is temperature effective value processed to obtain the temperature correction amount.

[0050] As a further specific description, the specific steps of judging whether to perform temperature drift compensation optimization are as follows:

[0051] If the sample average temperature is greater than the preset sample temperature maximum value, the harmonic average of the signal interference correction amount and the temperature correction amount is used to avoid overcompensation or undercompensation caused by a single factor, the harmonic average result is temperature effective value processed to obtain the temperature compensation amount, the difference between the current sample temperature and the temperature compensation amount is calculated to reduce the sample temperature, the sample temperature adjustment and the ferromagnetic resonance signal stability are balanced, the temperature compensation amount can both reduce the temperature and suppress new interference caused by sudden temperature drop, and the sample is cooled by a cooler, wherein the cooler is located near the sample and establishes a close heat exchange relationship with the sample through a specific sample holder and a pipe (such as a cooling gas pipe).

[0052] It should be further noted that the signal interference correction amount represents the difference between the ferromagnetic resonance signal interference coefficient and the ferromagnetic resonance signal interference set value, the temperature correction amount represents the difference between the sample average temperature and the preset sample temperature maximum value, and the temperature effective value processing represents rounding the result of the harmonic mean to two decimal places to ensure that the sample temperature can be adjusted. The main purpose of retaining two decimal places is to ensure the actual operability of the temperature compensation amount while ensuring the accuracy of the calculation.

[0053] If the sample average temperature is within the preset sample temperature standard interval, it means that the temperature of the sample is considered to be in a stable and suitable state, which can meet the requirements of the ferromagnetic resonance signal test, and no temperature drift compensation optimization is performed to avoid unnecessary intervention. The preset sample temperature standard interval represents a closed interval formed by the preset sample temperature minimum value and the preset sample temperature maximum value.

[0054] If the sample average temperature is less than the preset sample temperature minimum value, the harmonic average result of the signal interference correction amount and the temperature influence amount is subjected to temperature effective value processing to obtain the temperature correction amount. The result of adding the current sample temperature and the temperature correction amount is used to increase the sample temperature, which can eliminate the problem of sample magnet performance degradation and ferromagnetic resonance signal attenuation caused by low temperature. The sample is heated by a heater to compensate for the physical property changes of the sample itself caused by low temperature (such as material thermal expansion and contraction, and changes in electrical conductivity), so that the sample quickly returns to the standard temperature. At the data processing level, the measurement error caused by sample temperature interference is eliminated. The temperature influence amount represents the difference between the preset sample temperature minimum value and the sample average temperature.

[0055] In this embodiment, an adaptive temperature regulation system is constructed through "dynamic quantitative deviation-differentiated compensation-high precision control", which significantly enhances the stability, energy saving and environmental adaptability of high-frequency testing. By adjusting the sample temperature to compensate for the physical property changes of the sample itself caused by low temperature (such as material thermal expansion and contraction, and changes in electrical conductivity), at the control level, it can drive the temperature control equipment (such as heating elements and semiconductor chillers) to perform reverse regulation; at the data processing level, it can calibrate the original signal output by the sensor and eliminate the measurement error caused by temperature interference.

[0056] It should be noted that, as Figure 7As shown, the flow chart of the coil current compensation optimization of the self-adaptive calibration high-frequency test method provided by the embodiment of the application, the specific logic is: comparing the average magnetic induction intensity judgment with the preset maximum magnetic induction intensity, if the average magnetic induction intensity judgment is greater than the preset maximum magnetic induction intensity, then the harmonic average result of the signal interference judgment correction amount and the magnetic induction intensity deviation correction amount is processed to obtain the coil current compensation amount, otherwise, it is judged whether the average magnetic induction intensity is in the preset magnetic induction intensity standard interval, if yes, no coil current compensation optimization is performed, otherwise, the harmonic average result of the signal interference judgment correction amount and the magnetic induction intensity deviation correction amount is processed to obtain the coil current correction amount.

[0057] As a further specific description, the specific steps of judging whether to perform coil current compensation optimization are:

[0058] Step one, if the temperature drift compensation optimization is performed, the ferromagnetic resonance signal interference coefficient reacquired after optimization is recorded as the ferromagnetic resonance signal interference judgment value, otherwise, it is recorded as the ferromagnetic resonance signal interference judgment value, wherein the ferromagnetic resonance signal interference coefficient reacquired after temperature drift compensation optimization is to obtain a real data reflecting the actual effect of temperature drift compensation optimization based on the current latest sample temperature state. The ferromagnetic resonance signal interference judgment value is the basis for the system to make accurate judgment and effective control subsequently, ensuring that the entire self-adaptive calibration process can be dynamically adjusted according to the actual situation, and finally achieving the goal of optimizing signal quality.

[0059] Step two, comparing the ferromagnetic resonance signal interference judgment value with the ferromagnetic resonance signal interference set value, if the ferromagnetic resonance signal interference judgment value is less than or equal to the ferromagnetic resonance signal interference set value, no coil current compensation optimization is performed, which means that the ferromagnetic resonance signal quality has been successfully optimized to an ideal state through the previous temperature drift compensation optimization, and no coil current compensation optimization is performed to avoid the risk and resource consumption that may be caused by unnecessary adjustment, otherwise, step three is executed.

[0060] Step three, if the average magnetic induction intensity is greater than the preset maximum magnetic induction intensity, the harmonic mean result of the signal interference judgment correction amount and the magnetic induction intensity deviation correction amount is determined to the first decimal place to determine the coil current compensation amount, avoiding over-regulation or under-regulation caused by a single factor, and the coil current compensation amount is accurate to the first decimal place in order to find a reasonable balance point between control accuracy and test accuracy, ensure that the magnetic field adjustment is accurate and efficient, while avoiding problems caused by excessive adjustment. The difference between the current coil current value and the coil current compensation amount is obtained through proportional-integral-derivative control to reduce the coil current value, effectively suppress the ferromagnetic resonance signal distortion caused by unstable coil current, real-time monitor the magnetic induction intensity and dynamically adjust the coil current, which can intervene in correction in time at the initial stage of abnormal magnetic field strength, prevent the sample from demagnetizing due to excessive magnetic field, effectively avoid test interruption or data invalidation, otherwise execute step four. The magnetic induction intensity deviation correction amount represents the difference between the average magnetic induction intensity and the preset maximum magnetic induction intensity, and the signal interference judgment correction amount represents the difference between the ferromagnetic resonance signal interference judgment value and the ferromagnetic resonance signal interference setting value.

[0061] Step four, if the average magnetic induction intensity is within the preset magnetic induction intensity standard interval, no coil current compensation optimization is performed, otherwise step five is executed. The preset magnetic induction intensity standard interval represents a closed interval formed by the preset minimum magnetic induction intensity and the preset maximum magnetic induction intensity.

[0062] Step five, if the average magnetic induction intensity is less than the preset minimum magnetic induction intensity, the harmonic mean result of the signal interference judgment correction amount and the magnetic induction intensity deviation correction amount is determined to the first decimal place to determine the coil current compensation amount, avoiding over-regulation or under-regulation caused by a single factor, obtaining the coil current correction amount, and the result of adding the current coil current value and the coil current correction amount to enhance the coil current value, real-time response to magnetic field changes, reduce hysteresis effect, reduce measurement error caused by magnetic field drift, improve data accuracy. The magnetic induction intensity deviation correction amount represents the difference between the preset minimum magnetic induction intensity and the average magnetic induction intensity.

[0063] In this embodiment, through the step-by-step, condition-by-condition closed-loop control mechanism, the precise optimization of the coil current and the dynamic stability of the magnetic field strength are realized. Through real-time monitoring and hierarchical intervention, the scheme intervenes in the correction at the initial stage of the abnormality of the magnetic field strength, significantly improves the stability of the ferromagnetic resonance signal measurement and the stability of the equipment operation, reduces the risk of test interruption, and guarantees the continuity and efficiency of the experiment. Through real-time monitoring, calculation of the deviation, and application of the corresponding adjustment compensation coil current, a complete control loop is formed, which can actively respond to and correct the deviation. In magnetic measurement, the temperature change of the sample will affect its magnetic properties or signal output; in nuclear magnetic resonance, the temperature will affect the relaxation time of the sample. Therefore, simultaneous accurate control of the magnetic field and temperature is crucial for obtaining high-precision experimental results.

[0064] Further, the uniformity influence parameter specifically includes a magnetic flux deviation amount and a ferromagnetic resonance peak position deviation amount; and the specific steps of obtaining the magnetic field uniformity influence coefficient are as follows: obtaining the uniformity influence setting value, the uniformity influence correction amount, and the ferromagnetic resonance signal interference correction amount from the constructed high-frequency test database, the uniformity influence setting value specifically includes a magnetic flux deviation setting value and a ferromagnetic resonance peak position deviation setting value, the uniformity influence correction amount specifically includes a magnetic flux deviation correction amount and a ferromagnetic resonance peak position deviation correction amount; coupling the uniformity influence parameter and the proportion analysis result of the uniformity influence setting value after correction by the uniformity influence correction amount, denoted as the influence first index; if the signal interference optimization is performed, the ferromagnetic resonance signal interference coefficient reacquired after optimization is denoted as the to-be-compared ferromagnetic resonance signal interference coefficient, otherwise the current ferromagnetic resonance signal interference coefficient is denoted as the to-be-compared ferromagnetic resonance signal interference coefficient; the to-be-compared ferromagnetic resonance signal interference coefficient and the proportion analysis result of the ferromagnetic resonance signal interference setting value are corrected by the ferromagnetic resonance signal interference correction amount, denoted as the influence second index, wherein the proportion analysis result represents a division operation, the influence first index and the influence second index are coupled to obtain the magnetic field uniformity influence coefficient, and the greater the magnetic field uniformity influence coefficient, the greater the influence of the magnetic field non-uniformity on the ferromagnetic resonance signal measurement, i.e., the more non-uniform the magnetic field.

[0065] It needs to be explained that whether the temperature drift compensation optimization or the coil current compensation optimization is performed, these measures will change the factors affecting the ferromagnetic resonance signal (such as the temperature change amount) and affect the finally observed ferromagnetic resonance signal and the interference degree thereof, in order to ensure that the signal interference parameters used for subsequent comparison and decision can truly reflect the current system state, especially the state after the signal interference optimization, therefore the ferromagnetic resonance signal interference coefficient is reacquired and denoted as the to-be-compared ferromagnetic resonance signal interference coefficient.

[0066] In this embodiment, the specific limit expression of the influence first index is as follows:

[0067] ;

[0068] In the formula, Y represents the influence first index. P1 represents the magnetic flux deviation correction quantity obtained from the high-frequency test database, G represents the average magnetic flux obtained by averaging the magnetic flux of the sample in the magnetic field uniformity test measured in real time according to the fluxmeter, and the deviation of the average magnetic flux from the preset magnetic flux target value is recorded as the magnetic flux deviation quantity. The greater the magnetic flux deviation quantity, the more intense the magnetic field gradient or spatial variation, that is, the more non-uniform the magnetic field, and the greater the magnetic field uniformity influence coefficient. P2 represents the ferromagnetic resonance peak position deviation correction quantity obtained from the high-frequency test database, F represents the average ferromagnetic resonance peak obtained by averaging the ferromagnetic resonance peak in the magnetic field uniformity test measured in real time according to the ferromagnetic resonance spectrometer, and the comparison between the average ferromagnetic resonance peak and the preset ferromagnetic resonance peak standard value is recorded as the ferromagnetic resonance peak position deviation quantity. F1 represents the ferromagnetic resonance peak position deviation set value obtained from the high-frequency test database. The greater the ferromagnetic resonance peak position deviation quantity, the more significant the different resonance magnetic field regions in the sample, which will inevitably lead to signal broadening, and the greater the magnetic field uniformity influence coefficient.

[0069] The specific limiting expression of the influence second index is:

[0070] ;

[0071] In the formula, W represents the influence second index. P3 represents the ferromagnetic resonance signal interference correction quantity obtained from the high-frequency test database, L represents the ferromagnetic resonance signal interference coefficient to be compared, and L1 represents the ferromagnetic resonance signal interference set value obtained from the high-frequency test database. The greater the ferromagnetic resonance signal interference coefficient to be compared, the more resonance signals from different magnetic moments are superimposed, resulting in a widening of the originally sharp resonance peak, and the greater the magnetic field uniformity influence coefficient.

[0072] The specific limiting expression of the magnetic field uniformity influence coefficient is:

[0073] ;

[0074] In the formula, Q is the magnetic field uniformity influence coefficient.

[0075] It should be noted that the high-frequency test database stores three types of correction amounts corresponding to the uniformity influence parameters, respectively, the magnetic flux deviation correction amount, the ferromagnetic resonance peak position deviation correction amount, and the ferromagnetic resonance signal interference correction amount, the numerical range of which is generally between 0 and 1, and the sum of the three types of correction amounts is always 1. There is a pre-set mapping relationship between the uniformity influence parameters and the corresponding three types of correction amounts. This relationship can be a one-to-one correspondence, or a many-to-one correspondence. For example, in actual application, the real-time uniformity influence parameters can be substituted into the mapping relationship to quickly obtain the corresponding correction amount.

[0076] At the same time, the parameters involved in the magnetic field uniformity influence coefficient have correlations, which are as follows: the greater the magnetic flux deviation amount, that is, the more uneven the magnetic field, the greater the to-be-compared ferromagnetic resonance signal interference coefficient; the greater the magnetic flux deviation amount, the greater the ferromagnetic resonance peak position deviation amount caused by the magnetic field unevenness leading to serious signal distortion such as the appearance of strong spin wave secondary peaks, and the greater the to-be-compared ferromagnetic resonance signal interference coefficient; the greater the to-be-compared ferromagnetic resonance signal interference coefficient, the more serious the signal distortion, the more complex the ferromagnetic resonance peak shape, which is no longer a clear single peak, meaning that the magnetic field is uneven or has high microwave power, and the greater the ferromagnetic resonance peak position deviation amount.

[0077] In summary, by understanding the correlations among the magnetic flux deviation amount, the ferromagnetic resonance peak position deviation amount, and the to-be-compared ferromagnetic resonance signal interference coefficient, it is helpful to construct a complete mapping link of “physical field distortion-signal distortion-feature deviation” in ferromagnetic resonance testing, and improve the accurate calibration of ferromagnetic resonance signal errors; by understanding the positive and negative correlations between the magnetic flux deviation amount, the ferromagnetic resonance peak position deviation amount, and the magnetic field uniformity influence coefficient, it is helpful to construct a complete mapping link of “physical quantity deviation-signal feature deviation-uniformity influence coefficient quantification” in magnetic field uniformity optimization, and improve the adaptability of the sample and the magnetic flux distribution of the magnetic field.

[0078] Further, the specific steps for determining whether to perform magnetic field uniformity optimization are as follows: obtaining the magnetic field uniformity influence setting value from the high-frequency test database that has been constructed; if the magnetic field uniformity influence coefficient is less than or equal to the magnetic field uniformity influence setting value, no magnetic field uniformity optimization is performed; if the magnetic field uniformity influence coefficient is greater than the magnetic field uniformity influence setting value, magnetic field pre-setting is performed to determine the direction of the magnetic field change, and after determining the direction of the magnetic field change, whether to perform sample displacement optimization is determined according to the magnetic field change gradient.

[0079] Specifically, the specific process of performing magnetic field pre-setting is as follows:

[0080] S1, obtaining the magnetic field intensity of the current position of the sample during the magnetic field pre-setting process and comparing it with the magnetic field intensity of the starting position of the sample, wherein the magnetic field intensity of the current position and the magnetic field intensity of the starting position are measured by a fluxgate magnetometer.

[0081] S2, if the magnetic field intensity of the current position is greater than the magnetic field intensity of the starting position, it is determined that the moving direction of the sample during the magnetic field pre-setting process is correct, the magnetic field intensity change trend is increasing, and the movement in the current direction is continued.

[0082] S3, if the magnetic field intensity of the current position is equal to the magnetic field intensity of the starting position, it is determined that the sample has reached a local extreme point of the magnetic field, and the movement needs to be paused and the following operations are performed: if the local extreme point is a maximum point, the position of the sample is recorded as a candidate center point of the magnetic field uniform region; if the local extreme point is a minimum point, the moving direction of the sample is adjusted to the opposite direction of the magnetic field gradient.

[0083] S4, if the magnetic field intensity of the current position is less than the magnetic field intensity of the starting position, it is determined that the moving direction of the sample is incorrect and the movement in the current direction is stopped, the magnetic field intensity change trend is decreasing, and the movement in the current direction needs to be stopped immediately.

[0084] In addition, the magnetic field pre-setting also includes: judging whether there is a situation inconsistent with the determination result according to the magnetic field intensity change trend, if there is, sending an audible and visual warning prompt and displaying the abnormal position coordinates of the sample, otherwise continuing to move the sample in the current direction.

[0085] It needs to be explained that the known motor movement instruction is used (for example, moving a small distance in the positive direction of the X axis). After moving, the magnetic field intensity is measured again. The magnetic field intensity of the new position is compared with the magnetic field intensity of the previous position. If the magnetic field intensity of the new position is greater than the magnetic field intensity of the previous position, it means that the moving direction is correct and the magnetic field is increasing.

[0086] In this embodiment, by monitoring the position and magnetic field intensity change of the sample during the magnetic field pre-setting process in real time, an intelligent, closed-loop dynamic control and abnormal warning mechanism is constructed. Through this multi-dimensional and multi-level control strategy, not only the efficiency and accuracy of the magnetic field pre-setting are significantly improved, but also the resource waste and experimental error caused by incorrect direction or abnormal situation are effectively reduced, which lays a solid foundation for subsequent experiments or production processes relying on stable magnetic field environment.

[0087] Further, the specific process of judging whether to optimize the sample displacement amount is as follows:

[0088] If the magnetic field variation gradient is greater than the preset maximum magnetic field variation gradient, it means that the current distance from the magnetic field maximum is still a distance, or it is in a high gradient area of the gradient area, in order to cover the distance faster, reduce the number of steps required to reach the vicinity of the maximum magnetic induction intensity, improve the search efficiency, the harmonic mean result of the magnetic field uniformity correction amount and the variation gradient compensation amount is processed to obtain the sample movement compensation amount, the result of adding the current row sample position and the sample movement compensation amount is used as the position of the sample after movement, in order to increase the sample movement step, the motor drives the sample to move along the direction of the increasing magnetic field, the magnetic field uniformity correction amount represents the difference between the magnetic field uniformity influence coefficient and the magnetic field uniformity influence setting value, the variation gradient compensation amount represents the difference between the magnetic field variation gradient and the preset maximum magnetic field variation gradient, the movement effective value processing means that the result of the harmonic mean is accurate to one decimal place, in order to find a reasonable balance point between the motor control ability and the high-frequency test accuracy, and ensure that the sample can move to the position of the optimal magnetic field uniformity with the sample movement compensation amount to ensure that the sample displacement amount is adjustable.

[0089] If the magnetic field variation gradient is within the preset magnetic field variation gradient standard interval, it means that the magnetic field variation gradient in this range is considered to be appropriate or acceptable, and additional sample displacement amount optimization will cause disturbance to be introduced, because moving the sample will introduce unnecessary mechanical vibration or change the relative position between the sample and the magnetic field source, which will have a negative impact on high-frequency testing, so no sample displacement amount optimization is performed, and the preset magnetic field variation gradient standard interval represents a closed interval formed by the preset minimum magnetic field variation gradient and the preset maximum magnetic field variation gradient.

[0090] If the magnetic field variation gradient is less than the preset minimum magnetic field variation gradient, it indicates that the maximum magnetic induction intensity may have been approached, or it is in an area with very small magnetic field variation gradient, in order to more finely approach the position of the magnetic field maximum, improve the accuracy of the final positioning, and avoid missing the maximum magnetic induction intensity due to too large step size, the harmonic mean result of the magnetic field uniformity correction amount and the variation gradient correction amount is processed to obtain the sample movement correction amount, the result of subtracting the current row sample position from the sample movement correction amount is used as the position of the sample after movement, in order to reduce the sample movement step, the motor drives the sample to move along the direction of the increasing magnetic field, and the variation gradient correction amount represents the difference between the preset minimum magnetic field variation gradient and the magnetic field variation gradient.

[0091] As Figure 8Figure 1 shows a schematic diagram of installing a sample rod into a ColdTUBE low-temperature superconducting magnet system according to an embodiment of the present invention. When installing the sample rod into the low-temperature system, the following steps are required: First, install the sample onto the sample rod, and confirm that the magnetic field of the low-temperature superconducting magnet system is currently at zero and the temperature is at room temperature (295 K-300 K). Next, perform the cavity opening process, and the system will automatically inflate the cavity. Next, open the clamp and cover, and insert the FMR sample rod into the system cavity. Next, install the flange clamp to seal the cavity. Finally, perform the system purge process, and the sample rod installation is complete. Finally, connect the measurement cable to begin testing.

[0092] In this embodiment, this series of optimization and adjustment technologies ensures that the sample movement strategy can dynamically adapt under different magnetic field gradient conditions, taking into account both search efficiency and positioning accuracy, and realizing the intelligence and efficiency of the magnetic field optimization process.

[0093] like Figure 9 As shown, it is a structural diagram of a high-frequency test system with adaptive calibration provided by an embodiment of the present application. The high-frequency test system with adaptive calibration provided by an embodiment of the present application includes: a signal interference parameter quantification module, a signal interference optimization module, a uniformity influence parameter quantification module and a magnetic field uniformity optimization module: wherein, the signal interference parameter quantification module is used to use a three-dimensional magnetic Hall sensor to monitor the magnetic field strength of the moving slide and obtain the corresponding signal interference parameters before the high-frequency test. The three-dimensional magnetic Hall sensor is a cubic sensor provided with a plurality of Hall elements, which is configured to measure the three-dimensional air gap magnetic field and quantify the degree of interference of the ferromagnetic resonance signal according to the obtained signal interference parameters; the signal interference optimization module is used to determine whether to perform signal interference optimization based on the quantification result of the signal interference. If so, the magnetic field uniformity test is performed after the signal interference optimization is qualified. The signal interference optimization includes temperature drift compensation optimization to reduce the measurement error of ferromagnetic resonance signal caused by temperature interference, and coil current compensation optimization to reduce the measurement error of ferromagnetic resonance signal caused by coil current instability. The uniformity influencing parameter quantification module is used to combine the obtained uniformity influencing parameters to obtain the magnetic field uniformity influence coefficient to characterize the influence of magnetic field inhomogeneity on ferromagnetic resonance signal measurement. The magnetic field uniformity optimization module is used to determine whether to perform magnetic field uniformity optimization according to the magnetic field uniformity influence coefficient. If so, a high-frequency test is performed after the magnetic field uniformity optimization is qualified. Otherwise, a high-frequency test is performed directly. The magnetic field uniformity optimization means pre-setting the magnetic field to determine the direction of magnetic field change, and then optimizing the sample displacement to improve the adaptability of the sample to the magnetic field flux distribution.

[0094] It needs to be explained that when FMR (Ferromagnetic Resonance) test is carried out, the FMR test host needs to output, the phase-locked amplifier collects the voltage signal of the detector output, and the general measurement process is as follows: set the temperature to be tested; set the microwave frequency and power to be tested, set to FMR mode, turn on the microwave output; set the start-stop range and rate of the scanning magnetic field, start the variable field; during the variable field, the magnetic field and the readout voltage value of the phase-locked amplifier are periodically read at a fixed magnetic field step interval. When the magnetic field reaches the end value, the measurement is completed, and the microwave output is turned off.

[0095] As an embodiment of the second aspect, as Figure 10As shown, the ferromagnetic resonance test principle diagram of the high-frequency test method with adaptive calibration provided by the embodiment of the application, wherein the DC Field is a direct-current magnetic field, if the sample is a ferromagnetic sample, when the ferromagnetic sample is placed in a static magnetic field, if the magnetic moment of the ferromagnetic sample is inconsistent with the direction of the external magnetic field, the magnetic moment of the ferromagnetic sample will precess around the external magnetic field, at this time, due to the damping caused by magnetic anisotropy, defects and the like, the magnetic moment gradually approaches the direction of the external magnetic field in the precession process, and finally is consistent with the direction of the external magnetic field. Generally speaking, the intrinsic resonance frequency of the ferromagnetic material is mostly in the GHz order of magnitude, if a microwave magnetic field is applied outside the ferromagnetic sample, when the frequency of the microwave magnetic field is the same as the intrinsic resonance frequency of the material, the precession amplitude of the magnetic moment reaches the maximum, the energy absorption of the material to the microwave is the largest, that is, the ferromagnetic resonance occurs. The superconducting magnet will have residual magnetism after being used for a long time, that is, there will be an objective magnetic field in the uniform magnetic field region of the superconducting magnet coil when the power supply does not supply power to the superconducting magnet coil. The microwave source injects microwaves into the coplanar waveguide at a fixed frequency and a fixed power, in addition to applying a static magnetic field around the coplanar waveguide, a small amplitude alternating magnetic field in the same direction also needs to be applied. The power supply for applying the alternating magnetic field communicates synchronously with the phase-locked loop, the microwaves output by the coplanar waveguide are connected to the detector, the microwave power is converted into a voltage signal, and the voltage signal is tested by the phase-locked amplifier. The modulation of the small alternating magnetic field to the external magnetic field increases the test sensitivity, and the voltage signal obtained finally is the first derivative of the absorption spectrum with respect to the magnetic field. The alternating modulation current represents a small alternating current applied through the sample, which is modulated to generate a specific frequency and amplitude for exciting the electromagnetic response of the sample; the microwave signal is used for exciting and detecting the electromagnetic response of the sample at a higher frequency, the microwave input end sends the microwave signal to the sample, and the microwave output end receives the microwave signal reflected from the sample; the coplanar waveguide is a special transmission line structure for guiding the microwave signal to the sample and transmitting and processing the signal; the ferromagnetic resonance test host is responsible for controlling the operation of the entire high-frequency test system, including generating the required direct-current field, alternating modulation current and microwave signal, and collecting and processing the response signal from the sample; the phase-locked amplifier is a high-sensitivity signal processing device for detecting weak alternating signals and converting them into direct-current signals for subsequent data analysis and processing; the diode detector is used for converting high-frequency microwave signals into low-frequency signals; the PC-automation control and data acquisition is responsible for the automation control of the entire high-frequency test process, including setting test parameters, starting and stopping tests, real-time monitoring of the test process, and collecting and processing test data; the synchronization signal is used to ensure the coordinated work of each part in the system, especially in the case of multiple signal sources and detectors.

[0096] It should be noted that, as Figure 11As shown, the test software status bar interface and communication address setting interface of the high-frequency test method provided by the embodiment of the application, the blank box beside "Kelvinion mini", "Probe-", "Motor-" and "Magnet-" in the figure corresponds to the communication address. In the running process of the test software of the high-frequency test method, the status bar can set the communication address of the temperature controller, the magnet controller, the angle controller and other devices, and display and set the state of the whole test system, including the current temperature, the magnetic field, the angle position and the running position of the current Sequence. When clicking the corresponding state window, the corresponding setting instruction window will be popped up, which is used for setting the state parameters of the device in real time. For example, when clicking the Temperature window, the SetTemp window will be popped up to set the temperature, and after the setting is completed, the system temperature will immediately start to change according to the setting parameters. The Magnet and Motor windows also have the same function. Magnet represents the magnet; Field represents the magnetic field strength; VIT Temp refers to the temperature of the variable temperature insert; Probe Temp refers to the temperature of the probe; Rate refers to the change rate, for example, the change speed of the magnetic field or the temperature; Temperature refers to the temperature; Target Temp refers to the target temperature setting; Motor refers to the motor; Position refers to the current position of the motor; Target Pos refers to the target position setting; SequenceStatus refers to the sequence state; Line 3 represents the state of the third instruction or step in the sequence.

[0097] It should be noted that, as Figure 12As shown, a high-temperature-temperature test diagram of the high-frequency test method with adaptive calibration provided by the embodiment of the application has wide temperature range (300mK-500K) and wide frequency domain (1-67GHz) measurement capability. Among them, the room temperature test series function is comprehensive, and the system is composed of FMR test host, low temperature and room temperature test components, general components, etc. It can carry out FMR measurement of thin film / block material, and ST-FMR, spin pumping effect measurement of thin film / micro-nano device. With the help of low temperature test components and magnet system, it can also realize the function as low as 300mK. Rotating FMR / ST-FMR measurement can be conveniently achieved based on low temperature magnet test system or room temperature component, waveguide form is various, sample rod working frequency is 67GHz, wire bonding is included in the connection, non-magnetic piezoelectric motor needle pressing, optical channel laser, room temperature-low temperature end light fluorescence Raman test, etc. can also be selected. The probe movement is controlled by the piezoelectric motor adapted to the low temperature and ultra-high vacuum environment. The system uses vacuum sealed joint to connect the cable and external instrument, and the motor realizes the rotation angle; the support structure and signal transmission cable have rigid support and contain various optional cables; the support part can be connected by conversion joint; the low temperature part is the sample test area, and the variable temperature magnetic field environment provides vacuum, temperature and magnetic field conditions. From the temperature-time curve, it can be seen that the temperature changes at different positions (frame center, bottom, upper part, etc.) during the test process, reflecting that the system can accurately control and monitor the temperature field, helping to carry out comprehensive and accurate ferromagnetic resonance related test research on the magnetic properties of materials under wide temperature conditions, and adapting to various commercial low temperature superconducting magnet platforms, providing strong support for scientific research and material analysis. Figure 12

[0098] It needs to be noted that the probe type ST-FMR test system can realize frequency continuous change test in the adapted low temperature, magnetic field and other environments by inheriting the signal source, and carry out FMR measurement. The system structure is composed of a low temperature frame, which carries multiple direction piezoelectric motors (X, Y, Z direction, etc.), accurately controls the motion of STFMR devices, high frequency probes and sample tables processed by micro-nano, and rotates the piezoelectric motor to help adjust the sample angle. Low temperature high frequency cable guarantees signal transmission, observation window / low temperature objective lens / can introduce optical test means through optical fiber. It can carry out ferromagnetic resonance, spin transfer torque ferromagnetic resonance, spin pumping effect test on thin film, block material and micro-nano device in wide temperature range (300mK-500K), wide frequency domain (1-67GHz), realize accurate alignment of probe and sample, parameter regulation through multi-direction motor cooperation, and provide high precision, multi-functional test platform for studying material magnetism and exploring spin related physical mechanism, which meets the needs of in-depth analysis of micro-nano scale magnetism in scientific research.

[0099] ​The above merely illustrates the specific embodiments of the present application, but the protection scope of the present application is not limited thereto, any person skilled in the art can easily think of the changes or replacements within the technical range disclosed by the present application, which should be covered in the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A method of self-adapting calibration for high frequency testing, characterized in that, The method comprises the following steps: Before high-frequency testing, a three-dimensional magnetic sensitive Hall sensor is used to monitor the magnetic field intensity of the moving slide table and obtain corresponding signal interference parameters, and meanwhile, the degree of interference of the ferromagnetic resonance signal is quantified according to the obtained signal interference parameters; According to the quantification result of the signal interference, it is judged whether to perform signal interference optimization, if yes, after the signal interference optimization is qualified, the magnetic field uniformity test is performed, otherwise, the magnetic field uniformity test is directly performed and uniformity influence parameters are obtained, the signal interference optimization means that temperature drift compensation optimization is performed to reduce the measurement error of the ferromagnetic resonance signal caused by temperature interference, and coil current compensation optimization is performed to reduce the measurement error of the ferromagnetic resonance signal caused by unstable coil current; The magnetic field uniformity influence coefficient is obtained by combining the obtained uniformity influence parameters to represent the influence degree of the magnetic field non-uniformity on the ferromagnetic resonance signal measurement; According to the magnetic field uniformity influence coefficient, it is judged whether to perform magnetic field uniformity optimization, if yes, after the magnetic field uniformity optimization is qualified, the high-frequency test is performed, otherwise, the high-frequency test is directly performed, the magnetic field uniformity optimization means that the magnetic field pre-setting is performed to determine the direction of the magnetic field change, and then the sample displacement amount optimization is performed to improve the adaptation degree of the sample and the magnetic field magnetic flux distribution.

2. The method of claim 1, wherein, The signal interference parameters specifically include a sample rod inclination angle, a microwave frequency and a temperature change amount; The degree of interference of the ferromagnetic resonance signal is quantified according to the obtained signal interference parameters, specifically: the signal interference set value and the signal interference correction amount are obtained from the high-frequency test database constructed, the signal interference parameter and the signal interference set value are corrected by the signal interference correction amount, and the ferromagnetic resonance signal interference coefficient is obtained through the proportion analysis result. The signal interference set value specifically includes a sample rod inclination angle set value, a microwave frequency set value and a temperature change amount set value, and the signal interference correction amount specifically includes a sample rod inclination angle correction amount, a microwave frequency correction amount and a temperature change amount correction amount. The ferromagnetic resonance signal interference coefficient represents the data of the degree of interference of the ferromagnetic resonance signal reflected by the signal interference parameter and the signal interference set value.

3. The method of claim 1, wherein, The specific judgment steps of judging whether to perform signal interference optimization are: The ferromagnetic resonance signal interference set value is obtained from the high-frequency test database constructed; If the ferromagnetic resonance signal interference coefficient is less than or equal to the ferromagnetic resonance signal interference set value, the signal interference optimization is not performed; If the ferromagnetic resonance signal interference coefficient is greater than the ferromagnetic resonance signal interference set value, it is judged whether to perform temperature drift compensation optimization according to the average temperature of the sample, if yes, it is judged whether to perform coil current compensation optimization after the temperature drift compensation optimization is performed, otherwise, it is directly judged whether to perform coil current compensation optimization; The average temperature of the sample represents the average value of the temperature of the sample at the wide temperature range test time point.

4. The method of claim 3, wherein, The specific steps of judging whether to perform temperature drift compensation optimization are: If the sample average temperature is greater than the preset sample temperature maximum value, a harmonic average result of the signal interference correction quantity and the temperature correction quantity is subjected to temperature effective value processing to obtain a temperature compensation quantity, and a difference result between the current sample temperature and the temperature compensation quantity is used to reduce the sample temperature, the signal interference correction quantity represents a deviation degree of the ferromagnetic resonance signal interference coefficient from the ferromagnetic resonance signal interference set value, and the temperature correction quantity represents a deviation degree of the sample average temperature from the preset sample temperature maximum value; If the sample average temperature is within the preset sample temperature standard interval, temperature drift compensation optimization is not performed, and the preset sample temperature standard interval represents a closed interval formed by the preset sample temperature minimum value and the preset sample temperature maximum value; If the sample average temperature is less than the preset sample temperature minimum value, a harmonic average result of the signal interference correction quantity and the temperature influence quantity is subjected to temperature effective value processing to obtain a temperature correction quantity, and an addition result of the current sample temperature and the temperature compensation quantity is used to increase the sample temperature, and the temperature influence quantity represents a deviation degree of the preset sample temperature minimum value from the sample average temperature.

5. The method of claim 3, wherein the high frequency test is performed at a frequency of 1 MHz or higher. The specific steps of determining whether to perform the coil current compensation optimization are as follows: Step one, if the temperature drift compensation optimization is performed, the ferromagnetic resonance signal interference coefficient reacquired after optimization is recorded as the ferromagnetic resonance signal interference determination value, otherwise, the current ferromagnetic resonance signal interference coefficient is recorded as the ferromagnetic resonance signal interference determination value; Step two, the ferromagnetic resonance signal interference determination value is compared with the ferromagnetic resonance signal interference set value, if the ferromagnetic resonance signal interference determination value is less than or equal to the ferromagnetic resonance signal interference set value, the coil current compensation optimization is not performed, otherwise, step three is performed; Step three, if the average magnetic induction intensity is greater than the preset magnetic induction intensity maximum value, a harmonic average result of the signal interference determination correction quantity and the magnetic induction intensity deviation correction quantity is subjected to coil current effective value processing to obtain a coil current compensation quantity, and the coil current value is reduced based on the coil current compensation quantity, otherwise, step four is performed, the magnetic induction intensity deviation correction quantity represents a deviation degree of the average magnetic induction intensity from the preset magnetic induction intensity maximum value, and the signal interference determination correction quantity represents a deviation degree of the ferromagnetic resonance signal interference determination value from the ferromagnetic resonance signal interference set value; Step four, if the average magnetic induction intensity is within the preset magnetic induction intensity standard interval, the coil current compensation optimization is not performed, otherwise, step five is performed, and the preset magnetic induction intensity standard interval represents a closed interval formed by the preset magnetic induction intensity minimum value and the preset magnetic induction intensity maximum value; Step five, if the average magnetic induction intensity is less than the preset magnetic induction intensity minimum value, a harmonic average result of the signal interference determination correction quantity and the magnetic induction intensity deviation correction quantity is subjected to coil current effective value processing to obtain a coil current correction quantity, and the coil current value is enhanced based on the coil current correction quantity, and the magnetic induction intensity deviation correction quantity represents a deviation degree of the preset magnetic induction intensity minimum value from the average magnetic induction intensity.

6. The method of claim 1, wherein, The uniformity influence parameter specifically includes a magnetic flux deviation quantity and a ferromagnetic resonance peak position deviation quantity; The specific steps of obtaining the magnetic field uniformity influence coefficient are as follows: Obtaining the uniformity influence setting value, the uniformity influence correction amount and the ferromagnetic resonance signal interference correction amount from the constructed high-frequency test database, the uniformity influence setting value specifically includes a magnetic flux deviation setting value and a ferromagnetic resonance peak position deviation setting value, and the uniformity influence correction amount specifically includes a magnetic flux deviation correction amount and a ferromagnetic resonance peak position deviation correction amount; Coupling the uniformity influence parameter and the proportion analysis result of the uniformity influence setting value by the uniformity influence correction amount, denoted as an influence first index; If the signal interference optimization is performed, the ferromagnetic resonance signal interference coefficient reacquired after the signal interference optimization is denoted as a to-be-compared ferromagnetic resonance signal interference coefficient, otherwise the current ferromagnetic resonance signal interference coefficient is denoted as the to-be-compared ferromagnetic resonance signal interference coefficient; Correcting the to-be-compared ferromagnetic resonance signal interference coefficient and the proportion analysis result of the ferromagnetic resonance signal interference setting value by the ferromagnetic resonance signal interference correction amount, denoted as an influence second index, coupling the influence first index and the influence second index to obtain the magnetic field uniformity influence coefficient.

7. The method of claim 1, wherein, The specific steps of judging whether to perform the magnetic field uniformity optimization are as follows: Obtaining the magnetic field uniformity influence setting value from the constructed high-frequency test database; If the magnetic field uniformity influence coefficient is less than or equal to the magnetic field uniformity influence setting value, the magnetic field uniformity optimization is not performed; If the magnetic field uniformity influence coefficient is greater than the magnetic field uniformity influence setting value, the magnetic field pre-setting is performed to determine the direction of the magnetic field change, and then whether to perform the sample displacement optimization is judged according to the magnetic field change gradient.

8. The method of claim 7, wherein, The specific process of performing the magnetic field pre-setting is as follows: S1, obtaining the magnetic field intensity of the current position of the sample in the magnetic field pre-setting process and comparing it with the magnetic field intensity of the starting position of the sample; S2, if the magnetic field intensity of the current position is greater than that of the starting position, it is determined that the moving direction of the sample in the magnetic field pre-setting process is correct; S3, if the magnetic field intensity of the current position is equal to that of the starting position, it is determined that the sample has reached a local extreme point of the magnetic field; S4, if the magnetic field intensity of the current position is less than that of the starting position, it is determined that the moving direction of the sample is incorrect and the movement in the current direction is stopped; The magnetic field pre-setting further includes judging whether there is a situation inconsistent with the determination result according to the magnetic field intensity change trend, if there is, sending an audible and light pre-warning prompt and displaying the abnormal position coordinates of the sample, otherwise continuing to move the sample in the current direction.

9. The method of claim 7, wherein the high frequency test is performed at a frequency of 1 MHz or higher. The specific process of judging whether to perform the sample displacement optimization is as follows: If the magnetic field change gradient is greater than the preset maximum magnetic field change gradient, the harmonic average result of the magnetic field uniformity correction amount and the change gradient compensation amount is subjected to a moving amount effective value processing to obtain a sample moving compensation amount, the sample position is adjusted based on the sample moving compensation amount, the magnetic field uniformity correction amount represents the deviation degree of the magnetic field uniformity influence coefficient from the magnetic field uniformity influence setting value, and the change gradient compensation amount represents the deviation degree of the magnetic field change gradient from the preset maximum magnetic field change gradient. If the magnetic field variation gradient is within a preset magnetic field variation gradient standard interval, i.e., a closed interval formed by a preset magnetic field variation gradient minimum value and a preset magnetic field variation gradient maximum value, no sample displacement optimization is performed. If the magnetic field variation gradient is less than the preset magnetic field variation gradient minimum value, a harmonic mean result of the magnetic field uniformity correction amount and the variation gradient correction amount is subjected to a moving amount effective value processing to obtain a sample moving correction amount, and a sample position moving adjustment is performed based on the sample moving correction amount, wherein the variation gradient correction amount represents a deviation degree of the preset magnetic field variation gradient minimum value and the magnetic field variation gradient.

10. A self-adapting calibrated high frequency test system for implementing the high frequency test method according to any one of claims 1 to 9, characterized in that, The system comprises a signal interference parameter quantification module, a signal interference optimization module, a uniformity influence parameter quantification module, and a magnetic field uniformity optimization module. The signal interference parameter quantification module is configured to monitor the magnetic field intensity of the moving slide table and obtain corresponding signal interference parameters before high-frequency testing by using a three-dimensional magnetic sensitive Hall sensor. The signal interference optimization module is configured to determine whether to perform signal interference optimization according to the quantification result of the signal interference, and if yes, perform magnetic field uniformity testing after signal interference optimization is qualified, otherwise, directly perform magnetic field uniformity testing and obtain uniformity influence parameters. The uniformity influence parameter quantification module is configured to obtain a magnetic field uniformity influence coefficient to represent the influence degree of the magnetic field non-uniformity on the ferromagnetic resonance signal measurement in combination with the obtained uniformity influence parameters. The magnetic field uniformity optimization module is configured to determine whether to perform magnetic field uniformity optimization according to the magnetic field uniformity influence coefficient, and if yes, perform high-frequency testing after magnetic field uniformity optimization is qualified, otherwise, directly perform high-frequency testing.

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