Correction method and device suitable for Faraday optical rotation effect in magneto-optical spectrum test

Abstract

The invention relates to a correction method and device suitable for a Faraday optical rotation effect in a magneto-optical spectrum test, and the method comprises the steps: determining an angle corresponding to a first linear polarizer disposed on an excitation light path of a magneto-optical spectrum test system according to a target polarization state; according to a preset polarization configuration, determining a reference angle corresponding to a second linear polarizer arranged on a collection light path of the magneto-optical spectrum test system; respectively determining a first mapping relation between the angle of a first half-wave plate arranged on an excitation light path and different magnetic field intensities and a second mapping relation between the angle of a second half-wave plate arranged on a collection light path and different magnetic field intensities according to the reference angle under the condition that the magneto-optical spectrum test system is in different magnetic field intensities, and determining a calibration scheme of the magneto-optical spectrum test system under the target magnetic field intensity. According to the embodiment of the invention, the polarization error caused by the Faraday effect can be corrected by using the angle adjustment of the linear polarizer and the half-wave plate, and the applicability is high.

Description

Technical Field

[0001] The present invention relates to the technical field of magneto-optical spectroscopy measurement, and in particular to a correction method and device for Faraday rotation effect in magneto-optical spectroscopy testing. Background Art

[0002] In magneto-optical spectroscopy testing, by precisely controlling the polarization state of light, it is possible to analyze the deep mechanism of the interaction between light and matter, distinguish different types of optical and magnetic signals, and study the internal symmetry and coupling effects of low-dimensional materials and low-dimensional magnetic materials. However, the optical components (such as lenses, objective lenses, and optical windows) in the magneto-optical spectroscopy testing system may affect the polarization state of linearly polarized light due to the Faraday effect, resulting in systematic errors and affecting the accuracy and reliability of magneto-optical spectroscopy testing. Summary of the invention

[0003] In view of this, the present disclosure proposes a technical solution of a method and device for correcting the Faraday rotation effect in magneto-optical spectroscopy testing.

[0004] In one aspect of the present disclosure, a correction method for Faraday rotation effect in magneto-optical spectroscopy testing is provided, comprising: determining an angle corresponding to a first linear polarizer disposed in an excitation light path of a magneto-optical spectroscopy testing system according to a target polarization state, wherein the target polarization state includes the polarization angle of the target excitation light corresponding to the excitation light path; determining a reference angle corresponding to a second linear polarizer disposed in a collection light path of the magneto-optical spectroscopy testing system according to a preset polarization configuration, wherein the preset polarization configuration is used to indicate the relationship between the polarization direction of the target excitation light and the polarization direction of the collection light corresponding to the collection light path; and determining a reference angle corresponding to a second linear polarizer disposed in a collection light path of the magneto-optical spectroscopy testing system according to a preset polarization configuration when the magneto-optical spectroscopy testing system is in different magnetic field strengths. degrees, calibrating the first half-wave plate arranged in the excitation light path, and determining a first mapping relationship between the angle of the first half-wave plate and different magnetic field intensities; when the magneto-optical spectrum testing system is in different magnetic field intensities, calibrating the second half-wave plate arranged in the collection light path according to the reference angle, and determining a second mapping relationship between the angle of the second half-wave plate and different magnetic field intensities; determining a calibration scheme of the magneto-optical spectrum testing system under the target magnetic field intensity according to the first mapping relationship and the second mapping relationship, wherein the calibration scheme is used to indicate the angles of the first half-wave plate and the second half-wave plate when the magneto-optical spectrum testing system is in the target magnetic field intensity.

[0005] In a possible implementation, determining a reference angle corresponding to a second linear polarizer disposed in a collection light path of the magneto-optical spectroscopy testing system according to a preset polarization configuration includes: determining a third mapping relationship when only the first linear polarizer is disposed in the excitation light path and only the second linear polarizer is disposed in the collection light path, wherein the third mapping relationship is used to indicate the intensity of the collected light when the second linear polarizer is at different angles; and determining the reference angle according to the reference intensity of the collected light under the preset polarization configuration and the third mapping relationship.

[0006] In a possible implementation, when the magneto-optical spectrum test system is in different magnetic field strengths, the first half-wave plate arranged in the excitation light path is calibrated according to the reference angle to determine a first mapping relationship between the angle of the first half-wave plate and different magnetic field strengths, including: when the magneto-optical spectrum test system is in zero magnetic field strength, and the first linear polarizer and the first half-wave plate are arranged in the excitation light path, and the second linear polarizer is only arranged in the collection light path, the second linear polarizer is set at the reference angle, the angle of the first half-wave plate is adjusted until the light intensity of the collected light meets the reference light intensity, and the first initial angle corresponding to the first half-wave plate is determined; when the magneto-optical spectrum test system is in any non-zero magnetic field strength, and the first linear polarizer and the first half-wave plate are arranged in the excitation light path, and the second linear polarizer is only arranged in the collection light path, the second linear polarizer is set at the reference angle, the angle corresponding to the first half-wave plate is adjusted until the light intensity of the collected light meets the reference light intensity, and the first initial adjustment angle corresponding to the first half-wave plate under the magnetic field strength is determined; the first mapping relationship is determined according to the first initial angle and the first initial adjustment angle corresponding to the first half-wave plate under different magnetic field strengths.

[0007] In a possible implementation, the first mapping relationship is determined according to the first initial angle and the first initial adjustment angle corresponding to the first half-wave plate under different magnetic field intensities, including: when the magneto-optical spectrum testing system is in any non-zero magnetic field intensity, and the excitation light path is provided with the first linear polarizer and the first half-wave plate, and the collecting light path is provided with the second linear polarizer and the second half-wave plate, 1 / 2 of the first initial adjustment angle corresponding to the first half-wave plate under the magnetic field intensity is determined as the first target adjustment angle corresponding to the first half-wave plate under the magnetic field intensity; the first mapping relationship is determined according to the first initial angle and the first target adjustment angle corresponding to the first half-wave plate under different magnetic field intensities.

[0008] In a possible implementation, when the magneto-optical spectrum test system is in different magnetic field strengths, the second half-wave plate arranged in the collection light path is calibrated according to the reference angle to determine the second mapping relationship between the angle of the second half-wave plate and different magnetic field strengths, including: when the magneto-optical spectrum test system is in zero magnetic field strength, and the excitation light path is only provided with the first linear polarizer, and the collection light path is provided with the second linear polarizer and the second half-wave plate, the second linear polarizer is set at the reference angle, the angle of the second half-wave plate is adjusted until the light intensity of the collected light meets the reference light intensity, and the second initial angle corresponding to the second half-wave plate is determined; when the magneto-optical spectrum test system is in any non-zero magnetic field strength, and the excitation light path is only provided with the first linear polarizer, and the collection light path is provided with the second linear polarizer and the second half-wave plate, the second linear polarizer is set at the reference angle, the angle corresponding to the second half-wave plate is adjusted until the light intensity of the collected light meets the reference light intensity, and the second initial adjustment angle corresponding to the second half-wave plate under the magnetic field strength is determined; the second mapping relationship is determined according to the second initial angle and the second initial adjustment angle corresponding to the second half-wave plate under different magnetic field strengths.

[0009] In a possible implementation, the second mapping relationship is determined according to the second initial angle and the second initial adjustment angle corresponding to the second half-wave plate under different magnetic field intensities, including: when the magneto-optical spectrum testing system is in any non-zero magnetic field intensity, and the excitation light path is provided with the first linear polarizer and the first half-wave plate, and the collecting light path is provided with the second linear polarizer and the second half-wave plate, 1 / 2 of the second initial adjustment angle corresponding to the second half-wave plate under the magnetic field intensity is determined as the second target adjustment angle corresponding to the second half-wave plate under the magnetic field intensity; the second mapping relationship is determined according to the second initial angle and the second target adjustment angle corresponding to the second half-wave plate under different magnetic field intensities.

[0010] In a possible implementation manner, the light intensity of the collected light is determined by a power meter disposed behind the second linear polarizer.

[0011] In a possible implementation, the preset polarization configuration includes: the polarization direction corresponding to the target excitation light is parallel to the polarization direction corresponding to the collected light, or the polarization direction corresponding to the target excitation light is perpendicular to the polarization direction corresponding to the collected light.

[0012] In a possible implementation, during the calibration process of the second linear polarizer, the first half-wave plate, and the second half-wave plate, the collected light is reflected signal light of a substrate on which a test object is placed in the magneto-optical spectroscopy test system.

[0013] According to another aspect of the present disclosure, there is provided a correction device for Faraday rotation effect in magneto-optical spectroscopy testing, comprising: a first angle determination module, for determining an angle corresponding to a first linear polarizer disposed in an excitation light path of a magneto-optical spectroscopy testing system according to a target polarization state, wherein the target polarization state includes a polarization angle of a target excitation light corresponding to the excitation light path; a second angle determination module, for determining a reference angle corresponding to a second linear polarizer disposed in a collection light path of the magneto-optical spectroscopy testing system according to a preset polarization configuration, wherein the preset polarization configuration is used to indicate a relationship between a polarization direction of the target excitation light and a polarization direction of the collection light corresponding to the collection light path; a first mapping determination module, for determining, when the magneto-optical spectroscopy testing system is in different magnetic field intensities, According to the reference angle, the first half-wave plate arranged in the excitation light path is calibrated to determine the first mapping relationship between the angle of the first half-wave plate and different magnetic field intensities; a second mapping determination module is used to calibrate the second half-wave plate arranged in the collection light path according to the reference angle when the magneto-optical spectroscopy test system is in different magnetic field intensities, to determine the second mapping relationship between the angle of the second half-wave plate and different magnetic field intensities; a calibration scheme determination module is used to determine the calibration scheme of the magneto-optical spectroscopy test system under the target magnetic field intensity according to the first mapping relationship and the second mapping relationship, wherein the calibration scheme is used to indicate the angles of the first half-wave plate and the second half-wave plate when the magneto-optical spectroscopy test system is in the target magnetic field intensity.

[0014] In the disclosed embodiment, the angle corresponding to the first linear polarizer disposed in the excitation light path of the magneto-optical spectroscopy test system can be determined so that the polarization angle of the target excitation light corresponding to the excitation light path is in the target polarization state, thereby achieving the initialization of the target excitation light. The reference angle corresponding to the second linear polarizer disposed in the collection light path of the magneto-optical spectroscopy test system is determined so as to set the relationship between the polarization direction of the target excitation light and the polarization direction of the collection light corresponding to the collection light path to meet the preset polarization configuration, thereby providing a reliable basis for the subsequent calibration process. When the magneto-optical spectroscopy test system is in different magnetic field intensities, the first half-wave plate arranged in the excitation light path is calibrated according to the reference angle, and a first mapping relationship between the angle of the first half-wave plate and different magnetic field intensities can be determined, which is used as a basis for correcting the polarization error of the target excitation light caused by the Faraday rotation effect; when the magneto-optical spectroscopy test system is in different magnetic field intensities, the second half-wave plate arranged in the collection light path is calibrated according to the reference angle, and a second mapping relationship between the angle of the second half-wave plate and different magnetic field intensities can be determined, which is used as a basis for correcting the polarization error of the collection light caused by the Faraday rotation effect; based on the first mapping relationship and the second mapping relationship, a calibration scheme for the magneto-optical spectroscopy test system under the target magnetic field intensity can be determined to indicate the angles of the first half-wave plate and the second half-wave plate when the magneto-optical spectroscopy test system is in the target magnetic field intensity. Through the correction method of the embodiment of the present invention, the angle adjustment of the first linear polarizer, the second linear polarizer, the first half-wave plate and the second half-wave plate can be utilized to compensate for the polarization deviation of the target excitation light and the collected light caused by the Faraday effect, thereby avoiding the error accumulation caused by the change of polarization state during the magneto-optical spectrum test. The correction method has high correction accuracy and stability, and does not require the customization of special optical elements. The cost is low and it is easy to implement. It has high applicability and can be applied to a variety of different magneto-optical spectrum test systems and is suitable for different spectrum test requirements.

[0015] Further features and aspects of the present disclosure will become apparent from the following detailed description of exemplary embodiments with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate exemplary embodiments, features, and aspects of the disclosure and, together with the description, serve to explain the principles of the disclosure.

[0017] Figure 1 A flow chart showing a method for correcting the Faraday rotation effect in magneto-optical spectroscopy testing according to an embodiment of the present disclosure;

[0018] Figure 2 A schematic diagram showing a method for correcting the Faraday rotation effect in magneto-optical spectroscopy testing according to an embodiment of the present disclosure is shown;

[0019] Figure 3 A schematic structural diagram of a magneto-optical spectroscopy testing system according to an embodiment of the present disclosure is shown;

[0020] Figure 4 A schematic structural diagram of a magneto-optical spectroscopy testing system according to an embodiment of the present disclosure is shown;

[0021] Figure 5 A schematic structural diagram of a magneto-optical spectroscopy testing system according to an embodiment of the present disclosure is shown;

[0022] Figure 6 A block diagram of a correction device for Faraday rotation effect in magneto-optical spectroscopy testing according to an embodiment of the present disclosure is shown. DETAILED DESCRIPTION

[0023] Various exemplary embodiments, features and aspects of the present disclosure will be described in detail below with reference to the accompanying drawings. The same reference numerals in the accompanying drawings represent elements with the same or similar functions. Although various aspects of the embodiments are shown in the accompanying drawings, the drawings are not necessarily drawn to scale unless otherwise specified.

[0024] The word “exemplary” is used exclusively herein to mean “serving as an example, example, or illustration.” Any embodiment described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other embodiments.

[0025] The term "and / or" herein is only a description of the association relationship of the associated objects, indicating that there may be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the term "at least one" herein represents any combination of at least two of any one or more of a plurality of. For example, including at least one of A, B, and C can represent including any one or more elements selected from the set consisting of A, B, and C.

[0026] In addition, in order to better illustrate the present disclosure, numerous specific details are given in the following specific embodiments. It should be understood by those skilled in the art that the present disclosure can also be implemented without certain specific details. In some examples, methods, means, components and circuits well known to those skilled in the art are not described in detail in order to highlight the subject matter of the present disclosure.

[0027] As an important research method, magneto-optical spectroscopy is widely used in the fields of exploring new magnetic materials, spin electronics devices and quantum functional materials. Through the magneto-optical effect, key physical parameters of materials under different temperatures, magnetic fields and optical polarization conditions can be obtained non-destructively, such as spin alignment, spin-phonon coupling, exciton energy and exciton dynamics evolution. Among them, magneto-optical Raman spectroscopy, fluorescence spectroscopy and magneto-optical Kerr spectroscopy are the core methods of magneto-optical spectroscopy research.

[0028] In magneto-optical spectroscopy research, the polarization state of light is very important. The polarization state directly determines the way light interacts with the freedom of electrons, phonons, and spins in the material, thus providing a basis for revealing the symmetry and magnetic interaction of the material. By precisely controlling the polarization state of light, it is possible to analyze the deep mechanism of the interaction between light and matter, distinguish different types of optical and magnetic signals, and study the internal symmetry and coupling effects of low-dimensional materials and low-dimensional magnetic materials. This is of great significance for promoting technical fields such as the development of spin-based quantum devices and the exploration of new functional materials.

[0029] However, in polarized magneto-optical spectroscopy testing, the optical elements in the system (such as lenses, objectives, and optical windows, etc.) may cause the polarization state of linearly polarized light to change due to the Faraday effect under the action of an external magnetic field, thereby introducing systematic errors. The Faraday effect is a polarization rotation phenomenon of linearly polarized light induced by an external magnetic field. When linearly polarized light passes through a medium where a magnetic field is applied along the direction of light propagation, its polarization plane rotates. The rotation angle is proportional to the Verdet constant, optical path length, and magnetic field strength of the medium, and is also affected by parameters such as the wavelength and temperature of the light. In magneto-optical spectroscopy testing, the optical elements (especially the objective lens, etc.) close to the sample may cause significant polarization rotation of the linearly polarized light due to the presence of a residual magnetic field, causing the polarization state of the actual incident light on the sample to deviate from the original setting, thereby affecting the interaction between light and the sample, causing the test signal (such as Raman scattering or fluorescence) to deviate from the true value.

[0030] In the prior art, high-performance optical elements or polarization correction and compensation methods are usually used to correct the system errors introduced by the Faraday effect, thereby improving the accuracy of magneto-optical spectroscopy testing. For example, the use of objective lenses and optical windows with low Verdet constants and strong resistance to magnetic field interference can reduce the influence of the Faraday effect. However, the cost of such high-performance optical elements is relatively high, and their compatibility with existing test systems is poor, making it difficult to simultaneously meet complex test conditions such as low temperature, strong magnetic field, and high resolution. In addition, the Faraday effect is a ubiquitous optical phenomenon. The use of low Verdet constant elements can only reduce the polarization rotation angle, but cannot fundamentally eliminate the interference of the effect; under strong magnetic field conditions, since the rotation angle of the Faraday effect is linearly related to the magnetic field strength, its influence is still significant.

[0031] The prior art also proposes to use circularly polarized light as excitation light to avoid the influence of the Faraday effect. Although this method can reduce the influence of the Faraday effect, circularly polarized light excitation light is not suitable for all test scenarios. In some test scenarios, linearly polarized light must be used for excitation to detect the properties of the sample to be tested, resulting in poor applicability of this method.

[0032] The prior art also proposes a method of compensating the Faraday effect by utilizing the symmetry characteristics of the sample to be tested. Although this method can achieve correction under certain conditions, it relies on the symmetry characteristics of the sample to be tested and also lacks universality.

[0033] In view of this, the present disclosure provides a correction method for the Faraday rotation effect in magneto-optical spectroscopy testing. By introducing two linear polarizers and two half-wave plates in the external non-magnetic optical path of the magneto-optical spectroscopy testing system, the polarization errors of the excitation light and the collection light caused by the Faraday effect can be accurately compensated by using the flexible and precise adjustment of the linear polarizer angle and the half-wave plate angle, so as to ensure the consistency of the polarization state in the magneto-optical spectroscopy testing. The correction method of the present disclosure has high applicability and can be applied to a variety of different magneto-optical spectroscopy testing systems; and the correction method of the present disclosure does not require the customization of special optical elements, and is low in cost and easy to implement. The correction method of the present disclosure for the Faraday rotation effect in magneto-optical spectroscopy testing provided by the present disclosure is described in detail below.

[0034] Figure 1 A flow chart of a method for correcting the Faraday rotation effect in magneto-optical spectroscopy testing according to an embodiment of the present disclosure is shown. The method for correcting the Faraday rotation effect in magneto-optical spectroscopy testing can be executed by an electronic device such as a terminal device or a server. The terminal device can be a user equipment (UE), a mobile device, a user terminal, a terminal, a cellular phone, a cordless phone, a personal digital assistant (PDA), a handheld device, a computing device, a vehicle-mounted device, a wearable device, etc. The method for correcting the Faraday rotation effect in magneto-optical spectroscopy testing can be implemented by a processor calling computer-readable instructions stored in a memory. Alternatively, the method for correcting the Faraday rotation effect in magneto-optical spectroscopy testing can be executed by a server. Figure 1 As shown, the correction method for the Faraday rotation effect in magneto-optical spectroscopy testing includes:

[0035] In step S11, the angle corresponding to the first linear polarizer disposed in the excitation light path of the magneto-optical spectroscopy testing system is determined according to the target polarization state, wherein the target polarization state includes the polarization angle of the target excitation light corresponding to the excitation light path.

[0036] The magneto-optical spectroscopy test system here can represent any test system for implementing magneto-optical spectroscopy test, and its specific form can be flexibly set according to actual use requirements, for example, it can be a magneto-optical Raman spectroscopy test system, a magneto-optical fluorescence spectroscopy test system, etc., and the present disclosure does not make specific limitations on this. It should be noted that the excitation optical path of the magneto-optical spectroscopy test system is a non-magnetic optical path that is not covered by the magnetic field.

[0037] The target polarization state can represent the polarization state of the target excitation light required for magneto-optical spectroscopy testing, and is used to indicate the polarization angle of the target excitation light. The specific content of the target polarization state, that is, the specific polarization angle, can be flexibly set according to actual usage requirements, and the present disclosure does not make specific limitations on this.

[0038] According to the target polarization state, the angle corresponding to the first linear polarizer set in the excitation light path of the magneto-optical spectrum test system can be determined, so that the first linear polarizer can be used to initialize the target excitation light for subsequent magneto-optical spectrum testing. The specific form of the first linear polarizer can refer to the implementation in the related art, and the present disclosure does not specifically limit this.

[0039] Figure 2 FIG. 1 is a schematic diagram showing a method for correcting the Faraday rotation effect in magneto-optical spectroscopy according to an embodiment of the present disclosure. Figure 2 As shown, a first linear polarizer 201 is provided in the excitation light path corresponding to the magneto-optical spectroscopy test system 200. After the initial excitation light with an initial polarization state or without a polarization state is incident on the first linear polarizer 201, it will be adjusted to a target excitation light satisfying the target polarization state under the action of the first linear polarizer. The specific form of the initial excitation light and the source of the initial excitation light here can refer to the implementation in the related art, and the present disclosure does not make specific limitations on this.

[0040] The equipment environment of the magneto-optical spectroscopy testing system (including the ambient temperature corresponding to each optical element, etc.) and the specific method of applying the magnetic field of the magneto-optical spectroscopy testing system can be flexibly set according to actual usage requirements, and the present disclosure does not make specific limitations on this.

[0041] Figure 3 FIG. 2 is a schematic diagram showing the structure of a magneto-optical spectroscopy testing system according to an embodiment of the present disclosure. Figure 3 As shown, the external magnetic field of the magneto-optical spectroscopy testing system 300 is generated by a permanent magnet 301 in a room temperature environment, and the objective lens 302 and the sample to be tested 303 corresponding to the magneto-optical spectroscopy testing system 300 are both set in a room temperature environment.

[0042] Figure 4 FIG. 2 is a schematic diagram showing the structure of a magneto-optical spectroscopy testing system according to an embodiment of the present disclosure. Figure 4As shown, the external magnetic field of the magneto-optical spectroscopy testing system 400 is generated by a superconducting coil 402 disposed in a cryostat 401, and the objective lens 403 corresponding to the magneto-optical spectroscopy testing system 400 is disposed in a room temperature environment, and the sample to be tested 404 is disposed in a low temperature constant temperature environment in the cryostat 401. The target excitation light enters the cryostat 401 through an optical window 405 on the cryostat 401.

[0043] Figure 5 FIG. 2 is a schematic diagram showing the structure of a magneto-optical spectroscopy testing system according to an embodiment of the present disclosure. Figure 5 As shown, the external magnetic field of the magneto-optical spectroscopy test system 500 is generated by a superconducting coil 502 disposed in a cryostat 501, and the objective lens 503 and the sample to be tested 504 corresponding to the magneto-optical spectroscopy test system 500 are disposed in a low temperature constant temperature environment in the cryostat 501. The target excitation light first passes through a reflector 505 disposed in a room temperature environment, and then enters the cryostat 501 through a light window 506 on the cryostat 501.

[0044] In step S12, according to a preset polarization configuration, a reference angle corresponding to a second linear polarizer arranged in the collection light path of the magneto-optical spectroscopy testing system is determined, wherein the preset polarization configuration is used to indicate the relationship between the polarization direction of the target excitation light and the polarization direction of the collection light corresponding to the collection light path.

[0045] With the above Figure 2 For example, Figure 2 As shown, the collection light path of the magneto-optical spectroscopy test system 200 is provided with a second linear polarizer 202, which can be used to adjust the polarization state of the corresponding collected light in the collection light path. The specific form of the second linear polarizer can refer to the implementation in the related art, and the present disclosure does not specifically limit this. It should be noted that the collection light path of the magneto-optical spectroscopy test system is also a non-magnetic light path that is not covered by the magnetic field.

[0046] The preset polarization configuration is used to indicate the relationship between the polarization direction of the excitation light and the polarization direction of the collected light. Its specific form can be flexibly set according to actual usage requirements, and the present disclosure does not make specific limitations on this.

[0047] In a possible implementation, the preset polarization configuration includes: the polarization direction corresponding to the target excitation light is parallel to the polarization direction corresponding to the collection light, or the polarization direction corresponding to the target excitation light is perpendicular to the polarization direction corresponding to the collection light.

[0048] The polarization configuration in which the polarization direction corresponding to the target excitation light is parallel to the polarization direction corresponding to the collection light can be recorded as XX configuration, or Z(XX)Z configuration. The polarization configuration in which the polarization direction corresponding to the target excitation light is perpendicular to the polarization direction corresponding to the collection light can be recorded as XY configuration, or Z(XX)Z configuration. Among them, the first X represents the polarization direction corresponding to the target excitation light, and the second X, or Y, represents the polarization direction corresponding to the collection light.

[0049] According to the preset polarization configuration, the reference angle corresponding to the second linear polarizer can be determined so that the polarization direction corresponding to the collected light conforms to the preset polarization configuration to meet the requirements of magneto-optical spectrum testing.

[0050] The specific process of determining the reference angle corresponding to the second linear polarizer according to the preset polarization configuration will be described in detail later, and will not be elaborated here.

[0051] In step S13, when the magneto-optical spectroscopy test system is in different magnetic field strengths, the first half-wave plate arranged in the excitation light path is calibrated according to the reference angle to determine the first mapping relationship between the angle of the first half-wave plate and different magnetic field strengths.

[0052] With the above Figure 2 For example, Figure 2 As shown, the excitation optical path of the magneto-optical spectroscopy test system 200 is provided with a first half-wave plate 203, and in the case of zero magnetic field intensity, the fast axis corresponding to the first half-wave plate 203 is parallel to the first linear polarizer 201, which can be used to correct the polarization error of the target excitation light caused by the Faraday rotation effect. The specific form of the first half-wave plate can refer to the implementation in the related art, and the present disclosure does not make specific limitations on this.

[0053] When the magneto-optical spectroscopy test system is in any magnetic field strength, the first half-wave plate can be calibrated according to the reference angle corresponding to the second linear polarizer to determine the angle corresponding to the first half-wave plate when the magneto-optical spectroscopy test system is in the magnetic field strength.

[0054] According to the angle corresponding to the first half-wave plate when the magneto-optical spectroscopy test system is in different magnetic field intensities, a first mapping relationship between the angle of the first half-wave plate and different magnetic field intensities can be constructed, thereby providing a basis for correcting the polarization error of the target excitation light caused by the Faraday rotation effect.

[0055] The process of calibrating the first half-wave plate and determining the first mapping relationship between the angle of the first half-wave plate and different magnetic field intensities will be described in detail later, and will not be elaborated here.

[0056] In step S14, when the magneto-optical spectroscopy test system is in different magnetic field strengths, the second half-wave plate arranged in the collection light path is calibrated according to the reference angle to determine the second mapping relationship between the angle of the second half-wave plate and the different magnetic field strengths.

[0057] With the above Figure 2 For example, Figure 2 As shown, the collection optical path of the magneto-optical spectrum testing system 200 is provided with a second half-wave plate 204, and in the case of zero magnetic field intensity, the fast axis corresponding to the second half-wave plate 204 is parallel to the first linear polarizer 201, which can be used to correct the polarization error of the collected light caused by the Faraday rotation effect. The specific form of the second half-wave plate can refer to the implementation in the related art, and the present disclosure does not make specific limitations on this.

[0058] When the magneto-optical spectroscopy test system is in any magnetic field strength, the second half-wave plate can be calibrated according to the reference angle corresponding to the second linear polarizer to determine the angle corresponding to the second half-wave plate when the magneto-optical spectroscopy test system is in the magnetic field strength.

[0059] According to the angle corresponding to the second half-wave plate when the magneto-optical spectroscopy test system is in different magnetic field intensities, a second mapping relationship between the angle of the second half-wave plate and different magnetic field intensities can be constructed, thereby providing a basis for correcting the polarization error of the collected light caused by the Faraday rotation effect.

[0060] The process of calibrating the second half-wave plate and determining the second mapping relationship between the angle of the second half-wave plate and different magnetic field intensities will be described in detail later, and will not be elaborated here.

[0061] In step S15, a calibration scheme of the magneto-optical spectroscopy test system under the target magnetic field strength is determined according to the first mapping relationship and the second mapping relationship, wherein the calibration scheme is used to indicate the angles of the first half-wave plate and the second half-wave plate when the magneto-optical spectroscopy test system is under the target magnetic field strength.

[0062] When the magneto-optical spectroscopy test system is in a target magnetic field intensity, the angle of the first half-wave plate and the angle of the second half-wave plate can be determined respectively according to the first mapping relationship and the second mapping relationship, and then the calibration scheme of the magneto-optical spectroscopy test system under the target magnetic field intensity is determined, so as to correct the polarization error of the target excitation light and the polarization error of the collected light respectively, eliminate the influence of the Faraday rotation effect, and thus improve the accuracy and reliability of the magneto-optical spectroscopy test.

[0063] The specific method for determining the calibration scheme here can be flexibly set according to actual usage requirements and depends on the specific form of the magneto-optical spectroscopy testing system. The present disclosure does not make specific limitations on this.

[0064] In one example, when the magneto-optical spectroscopy test system is a magneto-optical Raman spectroscopy test system, the angles of the first half-wave plate and the second half-wave plate when the magneto-optical spectroscopy test system is under the target magnetic field intensity can be directly determined based on the first mapping relationship and the second mapping relationship, and used as a calibration scheme.

[0065] In a possible implementation, when the magneto-optical spectroscopy testing system is a magneto-optical fluorescence spectroscopy testing system, a calibration scheme for the magneto-optical spectroscopy testing system under a target magnetic field intensity is determined according to a first mapping relationship and a second mapping relationship, including: determining, according to the first mapping relationship and the second mapping relationship, a first target angle corresponding to the first half-wave plate and a second target angle corresponding to the second half-wave plate when the magneto-optical spectroscopy testing system is in the target magnetic field intensity; determining a wavelength correction coefficient between the target excitation light and the collected light according to the characteristic that the Faraday effect is approximately proportional to the square of the wavelength energy, wherein the wavelength correction coefficient is used to correct the second target angle; determining a calibration scheme according to the wavelength correction coefficient, the first target angle corresponding to the first half-wave plate, and the second target angle corresponding to the second half-wave plate.

[0066] Among them, the specific method for determining the wavelength correction coefficient between the target excitation light and the collected light can refer to the implementation method in the relevant technology, and the present disclosure does not make specific limitations on this.

[0067] In one example, the wavelength correction coefficient may be determined based on an empirical formula that the Faraday effect is inversely proportional to the square of the wavelength.

[0068] Specifically, the Faraday rotation angle θ caused by the Faraday effect is proportional to the product of the magnetic field intensity B corresponding to the magneto-optical fluorescence spectrum test system and the optical path L corresponding to the target excitation light. This relationship can be expressed as formula (1):

[0069] θ=VBL (1)

[0070] Wherein, V is the Verdet constant, which is used to quantify the responsiveness of any material to a magnetic field and can be determined by the Becquerel's formula. The Becquerel's formula can be expressed as formula (2):

[0071]

[0072] Where, e represents the charge of the electron; m e represents the mass of the electron; λ represents the wavelength of the target excitation light; represents the speed of light; dn / dλ is used to describe the dispersion relation corresponding to any material.

[0073] According to formula (2), the specific value of the Verdet constant V is affected by the material properties and temperature, as well as the wavelength of the target excitation light. In practical applications, it is usually impossible to accurately measure the Verdet constant V at each different wavelength. Therefore, the approximate relationship between the Verdet constant V and the wavelength λ can be analyzed through the Cauchy dispersion relation to calculate the Verdet constant V relatively accurately.

[0074] The Cauchy dispersion relation can be expressed as formula (3):

[0075]

[0076] By derivatizing formula (3), we can get formula (4):

[0077]

[0078] According to formula (2) and formula (4), the relationship between the Verdet constant V and the wavelength λ satisfies formula (5):

[0079]

[0080] According to formula (5), the Verdet constant V is approximately inversely proportional to the square of the wavelength λ, that is, it is proportional to the square of the photon energy of the target excitation light. Then, the wavelength correction coefficient can be determined through the above analysis process.

[0081] In one example, the energy of the excitation light is 2.33 eV (wavelength is 532 nm), the energy of the collection light is 1.38 eV (wavelength is 900 nm), and when the magneto-optical spectroscopy test system is in the target magnetic field intensity, the first target angle corresponding to the first half-wave plate is θ / 2, and the second target angle corresponding to the second half-wave plate is Based on the empirical formula of the Faraday effect and the inverse square of the wavelength, the wavelength correction factor can be determined to be (1.38 / 2.33) 2 , it can be determined that when the magneto-optical spectroscopy test system is in the target magnetic field strength, the calibration scheme is that the angle of the first half-wave plate is set to θ / 2, and the angle of the second half-wave plate is set to

[0082] In the disclosed embodiment, the angle corresponding to the first linear polarizer disposed in the excitation light path of the magneto-optical spectroscopy test system can be determined so that the polarization angle of the target excitation light corresponding to the excitation light path is in the target polarization state, thereby achieving the initialization of the target excitation light. The reference angle corresponding to the second linear polarizer disposed in the collection light path of the magneto-optical spectroscopy test system is determined so as to set the relationship between the polarization direction of the target excitation light and the polarization direction of the collection light corresponding to the collection light path to meet the preset polarization configuration, thereby providing a reliable basis for the subsequent calibration process. When the magneto-optical spectroscopy test system is in different magnetic field intensities, the first half-wave plate arranged in the excitation light path is calibrated according to the reference angle, and a first mapping relationship between the angle of the first half-wave plate and different magnetic field intensities can be determined, which is used as a basis for correcting the polarization error of the target excitation light caused by the Faraday rotation effect; when the magneto-optical spectroscopy test system is in different magnetic field intensities, the second half-wave plate arranged in the collection light path is calibrated according to the reference angle, and a second mapping relationship between the angle of the second half-wave plate and different magnetic field intensities can be determined, which is used as a basis for correcting the polarization error of the collection light caused by the Faraday rotation effect; based on the first mapping relationship and the second mapping relationship, a calibration scheme for the magneto-optical spectroscopy test system under the target magnetic field intensity can be determined to indicate the angles of the first half-wave plate and the second half-wave plate when the magneto-optical spectroscopy test system is in the target magnetic field intensity. Through the correction method of the embodiment of the present invention, the angle adjustment of the first linear polarizer, the second linear polarizer, the first half-wave plate and the second half-wave plate can be utilized to compensate for the polarization deviation of the target excitation light and the collected light caused by the Faraday effect, thereby avoiding the error accumulation caused by the change of polarization state during the magneto-optical spectrum test. The correction method has high correction accuracy and stability, and does not require the customization of special optical elements. The cost is low and it is easy to implement. It has high applicability and can be applied to a variety of different magneto-optical spectrum test systems and is suitable for different spectrum test requirements.

[0083] In one possible implementation, a reference angle corresponding to a second linear polarizer disposed in a collection light path of a magneto-optical spectroscopy testing system is determined according to a preset polarization configuration, including: when only a first linear polarizer is disposed in an excitation light path and only a second linear polarizer is disposed in a collection light path, a third mapping relationship is determined, wherein the third mapping relationship is used to indicate the intensity of the collected light when the second linear polarizer is at different angles; and a reference angle is determined according to the reference intensity of the collected light under the preset polarization configuration and the third mapping relationship.

[0084] In the case where only the first linear polarizer is provided in the excitation light path, and only the second linear polarizer is provided in the collection light path, the variation range corresponding to the intensity of the collected light can be determined by periodically adjusting the second linear polarizer. Generally, when the polarization direction of the collected light satisfies the XX configuration with the polarization direction of the target excitation light, the intensity of the collected light is the maximum value within the variation range; when the polarization direction of the collected light satisfies the XY configuration with the polarization direction of the target excitation light, the intensity of the collected light is the minimum value within the variation range.

[0085] Accordingly, by determining the intensity of the collected light when the second linear polarizer is at different angles, the third mapping relationship between the angle of the second linear polarizer and the intensity of the collected light can be analyzed, so that under different usage requirements, the reference angle corresponding to the second linear polarizer can be quickly determined according to the third mapping relationship and the reference intensity of the collected light under the preset polarization configuration. Among them, the specific method for determining the intensity of the collected light can be flexibly set according to the actual usage requirements, and the present disclosure does not specifically limit this.

[0086] In a possible implementation manner, the light intensity of the collected light is determined by a power meter disposed behind the second linear polarizer.

[0087] Along the propagation direction of the collected light, the intensity of the collected light can be detected in real time by a power meter arranged behind the second linear polarizer. It should be noted that there should be no other components between the second linear polarizer and the power meter, and the distance between the power meter and the second linear polarizer meets the preset threshold. The specific value of the preset threshold can be flexibly set according to actual usage requirements, and the present disclosure does not make specific limitations on this.

[0088] In a possible implementation, when the magneto-optical spectrum test system is in different magnetic field strengths, the first half-wave plate arranged in the excitation light path is calibrated according to a reference angle to determine a first mapping relationship between the angle of the first half-wave plate and different magnetic field strengths, including: when the magneto-optical spectrum test system is in zero magnetic field strength, and the first linear polarizer and the first half-wave plate are arranged in the excitation light path, and only the second linear polarizer is arranged in the collection light path, the second linear polarizer is arranged at the reference angle, the angle of the first half-wave plate is adjusted until the intensity of the collected light meets the reference intensity, and a first initial angle corresponding to the first half-wave plate is determined; when the magneto-optical spectrum test system is in any non-zero magnetic field strength, and the first linear polarizer and the first half-wave plate are arranged in the excitation light path, and only the second linear polarizer is arranged in the collection light path, the second linear polarizer is arranged at the reference angle, the angle corresponding to the first half-wave plate is adjusted until the intensity of the collected light meets the reference intensity, and a first initial adjustment angle corresponding to the first half-wave plate under the magnetic field strength is determined; the first mapping relationship is determined according to the first initial angle and the first initial adjustment angle corresponding to the first half-wave plate under different magnetic field strengths.

[0089] When the magneto-optical spectroscopy test system is in a zero magnetic field intensity, and the first linear polarizer and the first half-wave plate are set in the excitation light path, and only the second linear polarizer is set in the collection light path, the second linear polarizer is set at a reference angle, and the angle of the first half-wave plate can be adjusted until the intensity of the collected light meets the reference light intensity, and the first initial angle corresponding to the first half-wave plate is determined, which serves as a basis for calibrating the first half-wave plate when the magneto-optical spectroscopy test system is in a non-zero magnetic field intensity.

[0090] In one example, the preset polarization configuration is an XY configuration, the reference angle corresponding to the second linear polarizer is β, and the intensity of the collected light is detected by a power meter disposed behind the second linear polarizer.

[0091] Set the angle of the second linear polarizer to β, and adjust the angle of the first half-wave plate until the light intensity reading corresponding to the power meter is minimum, indicating that the light intensity of the collected light meets the reference light intensity corresponding to the XY configuration. The angle corresponding to the first half-wave plate at this time is determined as the first initial angle corresponding to the first half-wave plate.

[0092] Furthermore, for any preset polarization configuration, in order to improve the operability of the calibration process, reduce the difficulty of calibration, and improve the calibration accuracy, the angle of the second linear polarizer can be first set to β, and the angle corresponding to the first half-wave plate is determined based on the aforementioned process when the light intensity reading corresponding to the power meter is the smallest. Then, on the basis of this angle, the difference between the reference angle corresponding to the second linear polarizer in the preset polarization configuration and the angle β is added to determine the first initial angle corresponding to the first half-wave plate.

[0093] When the magneto-optical spectroscopy test system is in any non-zero magnetic field intensity, and the first linear polarizer and the first half-wave plate are set in the excitation light path, and only the second linear polarizer is set in the collection light path, the second linear polarizer is set at the reference angle, and the angle corresponding to the first half-wave plate can be adjusted with reference to the above record until the light intensity of the collected light meets the reference light intensity, and the first initial adjustment angle corresponding to the first half-wave plate under the magnetic field intensity is determined. Among them, the first initial adjustment angle corresponding to the first half-wave plate under any magnetic field intensity can represent the adjustment angle relative to the first initial angle.

[0094] Taking the above-mentioned preset polarization configuration as an XY configuration, the reference angle corresponding to the second linear polarizer is β, and detecting the intensity of the collected light by a power meter arranged behind the second linear polarizer as an example, the angle of the second linear polarizer is set to β, and the first half-wave plate is set to a first initial angle. On this basis, the angle of the first half-wave plate is adjusted until the light intensity reading corresponding to the power meter is minimum, indicating that the intensity of the collected light meets the reference light intensity corresponding to the XY configuration, and the first initial adjustment angle θ corresponding to the first half-wave plate is determined.

[0095] Similarly, for any preset polarization configuration, the angle of the second linear polarizer can be set to β first, and then the angle corresponding to the first half-wave plate when the light intensity reading corresponding to the power meter is minimum can be determined based on the above process. Then, based on this angle, the difference between the reference angle corresponding to the second linear polarizer in the preset polarization configuration and the angle β can be added to determine the first initial adjustment angle corresponding to the first half-wave plate.

[0096] By repeating the above calibration process multiple times for different magnetic field intensities, the first initial adjustment angle corresponding to the first half-wave plate under different magnetic field intensities can be determined, and then the first mapping relationship can be determined based on the first initial angle and the first initial adjustment angle corresponding to the first half-wave plate under different magnetic field intensities.

[0097] In a possible implementation, a first mapping relationship is determined based on a first initial angle and a first initial adjustment angle corresponding to the first half-wave plate under different magnetic field intensities, including: when the magneto-optical spectrum testing system is in any non-zero magnetic field intensity, and the excitation light path is provided with a first linear polarizer and a first half-wave plate, and the collection light path is provided with a second linear polarizer and a second half-wave plate, 1 / 2 of the first initial adjustment angle corresponding to the first half-wave plate under the magnetic field intensity is determined as the first target adjustment angle corresponding to the first half-wave plate under the magnetic field intensity; the first mapping relationship is determined based on the first initial angle and the first target adjustment angle corresponding to the first half-wave plate under different magnetic field intensities.

[0098] When the magneto-optical spectroscopy test system is in a zero magnetic field intensity, when the target excitation light enters the magnetic field through the optical element, the Faraday rotation effect will produce the first polarization rotation, that is, the polarization error corresponding to the target excitation light; and when the collected light leaves the magnetic field through the optical element, the Faraday rotation effect will produce the second polarization rotation, that is, the polarization error corresponding to the collected light.

[0099] Since in the calibration process for the first half-wave plate, the first linear polarizer and the first half-wave plate are set in the excitation light path, and only the second linear polarizer is set in the collection light path, at this time, the polarization adjustment produced by the target excitation light passing through the first half-wave plate is the total compensation of the polarization error corresponding to the target excitation light and the polarization error corresponding to the collection light, resulting in the polarization angle of the excitation light incident on the magneto-optical spectrum test system not meeting the polarization angle corresponding to the target polarization state, affecting the normal progress of the magneto-optical spectrum test. This is also the reason why the target excitation light and the collection light need to be calibrated separately in the actual magneto-optical spectrum test process.

[0100] Normally, under the same magnetic field intensity, the polarization error caused by the Faraday rotation effect remains unchanged, and the optical path that the target excitation light passes through after passing through the first half-wave plate and entering the magneto-optical spectrum test system is the same as the optical path that the collection light passes through before leaving the magneto-optical spectrum test system and entering the second half-wave plate. Therefore, in the normal magneto-optical spectrum test process, that is, when the magneto-optical spectrum test system is in any non-zero magnetic field intensity, and the first linear polarizer and the first half-wave plate are set in the excitation light path, and the second linear polarizer and the second half-wave plate are set in the collection light path, the first target adjustment angle corresponding to the first half-wave plate under the magnetic field intensity can be set to 1 / 2 of the first initial adjustment angle corresponding to the first half-wave plate under the magnetic field intensity, so that the polarization adjustment generated by the target excitation light passing through the first half-wave plate is only a compensation for the polarization error corresponding to the target excitation light.

[0101] In a possible implementation, when the magneto-optical spectrum test system is in different magnetic field strengths, the second half-wave plate arranged in the collection light path is calibrated according to a reference angle to determine a second mapping relationship between the angle of the second half-wave plate and different magnetic field strengths, including: when the magneto-optical spectrum test system is in zero magnetic field strength, and only the first linear polarizer is set in the excitation light path, and the second linear polarizer and the second half-wave plate are set in the collection light path, the second linear polarizer is set at the reference angle, the angle of the second half-wave plate is adjusted until the intensity of the collected light meets the reference intensity, and the second initial angle corresponding to the second half-wave plate is determined; when the magneto-optical spectrum test system is in any non-zero magnetic field strength, and only the first linear polarizer is set in the excitation light path, and the second linear polarizer and the second half-wave plate are set in the collection light path, the second linear polarizer is set at the reference angle, the angle corresponding to the second half-wave plate is adjusted until the intensity of the collected light meets the reference intensity, and the second initial adjustment angle corresponding to the second half-wave plate under the magnetic field strength is determined; the second mapping relationship is determined according to the second initial angle and the second initial adjustment angle corresponding to the second half-wave plate under different magnetic field strengths.

[0102] When the magneto-optical spectrum test system is in a zero magnetic field intensity, and only the first linear polarizer is set in the excitation light path, and the second linear polarizer and the second half-wave plate are set in the collection light path, the second linear polarizer is set at a reference angle, and the second half-wave plate set in the collection light path can be calibrated to determine the second initial angle corresponding to the second half-wave plate. The specific method can directly refer to the above-mentioned process of calibrating the first half-wave plate, which will not be repeated here.

[0103] Similarly, when the magneto-optical spectroscopy test system is in any non-zero magnetic field intensity, and only the first linear polarizer is set in the excitation light path, and the second linear polarizer and the second half-wave plate are set in the collection light path, the second linear polarizer is set at a reference angle, and the second half-wave plate set in the collection light path can be calibrated to determine the second initial adjustment angle corresponding to the second half-wave plate. The specific method can also directly refer to the above-mentioned process of calibrating the first half-wave plate, which will not be repeated here. Among them, the second initial adjustment angle corresponding to the second half-wave plate under any magnetic field intensity can represent the adjustment angle relative to the second initial angle.

[0104] By repeating the above calibration process multiple times for different magnetic field intensities, the second initial adjustment angle corresponding to the second half-wave plate under different magnetic field intensities can be determined, and then the second mapping relationship can be determined based on the second initial angle and the first initial adjustment angle corresponding to the second half-wave plate under different magnetic field intensities.

[0105] In a possible implementation, a second mapping relationship is determined based on a second initial angle and a second initial adjustment angle corresponding to the second half-wave plate under different magnetic field intensities, including: when the magneto-optical spectrum testing system is in any non-zero magnetic field intensity, and the excitation light path is provided with a first linear polarizer and a first half-wave plate, and the collection light path is provided with a second linear polarizer and a second half-wave plate, 1 / 2 of the second initial adjustment angle corresponding to the second half-wave plate under the magnetic field intensity is determined as the second target adjustment angle corresponding to the second half-wave plate under the magnetic field intensity; a second mapping relationship is determined based on the second initial angle and the second target adjustment angle corresponding to the second half-wave plate under different magnetic field intensities.

[0106] Similarly, since during the calibration process of the second half-wave plate, only the first linear polarizer is set in the excitation light path, and the second linear polarizer and the second half-wave plate are set in the collecting light path, at this time, the polarization adjustment produced by the target excitation light passing through the second half-wave plate is a total compensation for the polarization error corresponding to the target excitation light and the polarization error corresponding to the collecting light, resulting in the polarization angle of the collecting light passing through the second half-wave plate cannot accurately reflect the true polarization state of the collecting light emitted by the magneto-optical spectroscopy test system, affecting the accuracy of the test results.

[0107] Therefore, in the normal magneto-optical spectrum testing process, that is, when the magneto-optical spectrum testing system is in any non-zero magnetic field intensity, and the first linear polarizer and the first half-wave plate are set in the excitation light path, and the second linear polarizer and the second half-wave plate are set in the collecting light path, the second target adjustment angle corresponding to the second half-wave plate under the magnetic field intensity can be set to 1 / 2 of the second initial adjustment angle corresponding to the second half-wave plate under the magnetic field intensity, so that the polarization adjustment generated by the target excitation light passing through the second half-wave plate is only a compensation for the polarization error corresponding to the collected light.

[0108] Experimental verification shows that when the magneto-optical spectroscopy test system is in any non-zero magnetic field strength, and the first linear polarizer and the first half-wave plate are set in the excitation light path, and the second linear polarizer and the second half-wave plate are set in the collection light path, the second target adjustment angle corresponding to the second half-wave plate under the magnetic field strength is equal in magnitude and opposite in direction to the first target adjustment angle corresponding to the first half-wave plate under the magnetic field strength. For example, under any magnetic field strength, the first target adjustment angle corresponding to the first half-wave plate under the magnetic field strength is +θ / 2, then the second target adjustment angle corresponding to the second half-wave plate under the magnetic field strength is Among them, + means clockwise rotation, and - means counterclockwise rotation.

[0109] In a possible implementation, during the calibration process of the second linear polarizer, the first half-wave plate, and the second half-wave plate, the collected light is the reflected signal light of the substrate on which the test object is placed in the magneto-optical spectroscopy test system.

[0110] Experimental verification shows that the calibration scheme determined by the calibration method provided by the present disclosure when the reflected signal light of the substrate (such as a silicon wafer, etc.) next to the test object is used as the collected light for calibration is the same as the calibration scheme determined when the reflected signal light of a medium that does not introduce Faraday rotation, such as a gold film, is used as the collected light for calibration. In other words, for the same magneto-optical spectroscopy test system, when the calibration method provided by the present disclosure is used for calibration, it is not necessary to repeatedly adjust for different test objects, and it has high applicability and can be widely used in a variety of different application scenarios, and has application prospects in the fields of materials science, optics, and magnetism.

[0111] The specific material and form of the substrate here can be flexibly set according to actual use requirements, and the present disclosure does not specifically limit this. Preferably, the substrate is a medium such as a silicon wafer or a gold film set next to the sample to be tested that does not introduce Faraday rotation.

[0112] In the disclosed embodiment, the angle corresponding to the first linear polarizer disposed in the excitation light path of the magneto-optical spectroscopy test system can be determined so that the polarization angle of the target excitation light corresponding to the excitation light path is in the target polarization state, thereby achieving the initialization of the target excitation light. The reference angle corresponding to the second linear polarizer disposed in the collection light path of the magneto-optical spectroscopy test system is determined so as to set the relationship between the polarization direction of the target excitation light and the polarization direction of the collection light corresponding to the collection light path to meet the preset polarization configuration, thereby providing a reliable basis for the subsequent calibration process. When the magneto-optical spectroscopy test system is in different magnetic field intensities, the first half-wave plate arranged in the excitation light path is calibrated according to the reference angle, and a first mapping relationship between the angle of the first half-wave plate and different magnetic field intensities can be determined, which is used as a basis for correcting the polarization error of the target excitation light caused by the Faraday rotation effect; when the magneto-optical spectroscopy test system is in different magnetic field intensities, the second half-wave plate arranged in the collection light path is calibrated according to the reference angle, and a second mapping relationship between the angle of the second half-wave plate and different magnetic field intensities can be determined, which is used as a basis for correcting the polarization error of the collection light caused by the Faraday rotation effect; based on the first mapping relationship and the second mapping relationship, a calibration scheme for the magneto-optical spectroscopy test system under the target magnetic field intensity can be determined to indicate the angles of the first half-wave plate and the second half-wave plate when the magneto-optical spectroscopy test system is in the target magnetic field intensity. Through the correction method of the embodiment of the present disclosure, the angle adjustment of the first linear polarizer, the second linear polarizer, the first half-wave plate, and the second half-wave plate can be used to compensate for the polarization deviation of the target excitation light and the collected light caused by the Faraday effect, thereby avoiding the accumulation of errors caused by changes in the polarization state during the magneto-optical spectrum test. It has high correction accuracy and stability, and does not require the customization of special optical elements. It is low-cost and easy to implement, has high applicability, can be applied to a variety of different magneto-optical spectrum test systems, and is suitable for different spectrum test requirements. In addition, the collected light used in the correction process can directly use the reflected signal light of the substrate in the magneto-optical spectrum test system where the test object is placed, and does not need to be repeatedly adjusted for different samples to be tested, which can further improve applicability and reduce correction costs.

[0113] It can be understood that the above-mentioned various method embodiments mentioned in the present disclosure can be combined with each other to form a combined embodiment without violating the principle logic. Due to space limitations, the present disclosure will not repeat them. It can be understood by those skilled in the art that in the above-mentioned method of the specific implementation method, the specific execution order of each step should be determined according to its function and possible internal logic.

[0114] In addition, the present disclosure also provides a correction device for the Faraday rotation effect in magneto-optical spectroscopy testing, which can be used to implement any correction method for the Faraday rotation effect in magneto-optical spectroscopy testing provided by the present disclosure. The corresponding technical solutions and descriptions are referred to in the corresponding records of the method part and will not be repeated here.

[0115] Figure 6 FIG. 1 is a block diagram of a correction device for the Faraday rotation effect in magneto-optical spectroscopy according to an embodiment of the present disclosure. Figure 6 As shown, the device 600 includes:

[0116] A first angle determination module 601 is used to determine the angle corresponding to the first linear polarizer disposed in the excitation light path of the magneto-optical spectroscopy test system according to the target polarization state, wherein the target polarization state includes the polarization angle of the target excitation light corresponding to the excitation light path;

[0117] A second angle determination module 602 is used to determine a reference angle corresponding to a second linear polarizer disposed in a collection light path of the magneto-optical spectroscopy test system according to a preset polarization configuration, wherein the preset polarization configuration is used to indicate a relationship between a polarization direction of the target excitation light and a polarization direction of the collection light corresponding to the collection light path;

[0118] A first mapping determination module 603 is used to calibrate a first half-wave plate provided in an excitation optical path according to a reference angle when the magneto-optical spectroscopy test system is in different magnetic field intensities, and determine a first mapping relationship between the angle of the first half-wave plate and different magnetic field intensities;

[0119] A second mapping determination module 604 is used to calibrate the second half-wave plate provided in the collection light path according to the reference angle when the magneto-optical spectrum test system is in different magnetic field strengths, and determine a second mapping relationship between the angle of the second half-wave plate and different magnetic field strengths;

[0120] The calibration scheme determination module 605 is used to determine the calibration scheme of the magneto-optical spectroscopy test system under the target magnetic field strength according to the first mapping relationship and the second mapping relationship, wherein the calibration scheme is used to indicate the angles of the first half-wave plate and the second half-wave plate when the magneto-optical spectroscopy test system is under the target magnetic field strength.

[0121] In one possible implementation, the second angle determination module 602 is specifically used to: determine a third mapping relationship when only a first linear polarizer is set in the excitation light path and only a second linear polarizer is set in the collection light path, wherein the third mapping relationship is used to indicate the intensity of the collected light when the second linear polarizer is at different angles; determine a reference angle based on a reference intensity of the collected light under a preset polarization configuration and the third mapping relationship.

[0122] In one possible implementation, the first mapping determination module 603 is specifically used for: when the magneto-optical spectroscopy test system is in a zero magnetic field intensity, and the first linear polarizer and the first half-wave plate are set in the excitation light path, and only the second linear polarizer is set in the collection light path, the second linear polarizer is set at a reference angle, and the angle of the first half-wave plate is adjusted until the intensity of the collected light meets the reference light intensity, and the first initial angle corresponding to the first half-wave plate is determined; when the magneto-optical spectroscopy test system is in any non-zero magnetic field intensity, and the first linear polarizer and the first half-wave plate are set in the excitation light path, and only the second linear polarizer is set in the collection light path, the second linear polarizer is set at a reference angle, and the angle corresponding to the first half-wave plate is adjusted until the intensity of the collected light meets the reference light intensity, and the first initial adjustment angle corresponding to the first half-wave plate under the magnetic field intensity is determined; and the first mapping relationship is determined according to the first initial angle and the first initial adjustment angle corresponding to the first half-wave plate under different magnetic field intensities.

[0123] In a possible implementation, the first mapping determination module 603 is also used for: when the magneto-optical spectroscopy testing system is in any non-zero magnetic field intensity, and the excitation light path is provided with a first linear polarizer and a first half-wave plate, and the collection light path is provided with a second linear polarizer and a second half-wave plate, 1 / 2 of the first initial adjustment angle corresponding to the first half-wave plate under the magnetic field intensity is determined as the first target adjustment angle corresponding to the first half-wave plate under the magnetic field intensity; and the first mapping relationship is determined according to the first initial angle and the first target adjustment angle corresponding to the first half-wave plate under different magnetic field intensities.

[0124] In one possible implementation, the second mapping determination module 604 is specifically used for: when the magneto-optical spectroscopy test system is in a zero magnetic field intensity, and only the first linear polarizer is set in the excitation light path, and the second linear polarizer and the second half-wave plate are set in the collection light path, the second linear polarizer is set at a reference angle, and the angle of the second half-wave plate is adjusted until the intensity of the collected light meets the reference light intensity, and the second initial angle corresponding to the second half-wave plate is determined; when the magneto-optical spectroscopy test system is in any non-zero magnetic field intensity, and only the first linear polarizer is set in the excitation light path, and the second linear polarizer and the second half-wave plate are set in the collection light path, the second linear polarizer is set at a reference angle, and the angle corresponding to the second half-wave plate is adjusted until the intensity of the collected light meets the reference light intensity, and the second initial adjustment angle corresponding to the second half-wave plate under the magnetic field intensity is determined; the second mapping relationship is determined according to the second initial angle and the second initial adjustment angle corresponding to the second half-wave plate under different magnetic field intensities.

[0125] In one possible implementation, the second mapping determination module 604 is also used for: when the magneto-optical spectroscopy testing system is in any non-zero magnetic field intensity, and the excitation light path is provided with a first linear polarizer and a first half-wave plate, and the collection light path is provided with a second linear polarizer and a second half-wave plate, 1 / 2 of the second initial adjustment angle corresponding to the second half-wave plate under the magnetic field intensity is determined as the second target adjustment angle corresponding to the second half-wave plate under the magnetic field intensity; and the second mapping relationship is determined according to the second initial angle and the second target adjustment angle corresponding to the second half-wave plate under different magnetic field intensities.

[0126] In a possible implementation manner, the light intensity of the collected light is determined by a power meter disposed behind the second linear polarizer.

[0127] In a possible implementation, the preset polarization configuration includes: the polarization direction corresponding to the target excitation light is parallel to the polarization direction corresponding to the collection light, or the polarization direction corresponding to the target excitation light is perpendicular to the polarization direction corresponding to the collection light.

[0128] In a possible implementation, during the calibration process of the second linear polarizer, the first half-wave plate, and the second half-wave plate, the collected light is the reflected signal light of the substrate on which the test object is placed in the magneto-optical spectroscopy test system.

[0129] In some embodiments, the functions or modules included in the device provided by the embodiments of the present disclosure can be used to execute the method described in the above method embodiments. The specific implementation can refer to the description of the above method embodiments, and for the sake of brevity, it will not be repeated here.

[0130] The embodiments of the present disclosure have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and changes will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The selection of terms used herein is intended to best explain the principles of the embodiments, practical applications, or technical improvements in the market, or to enable other persons of ordinary skill in the art to understand the embodiments disclosed herein.

Claims

1. A correction method for Faraday rotation effect in magneto-optical spectroscopy, characterized in that: include: Determine the angle corresponding to the first linear polarizer disposed in the excitation light path of the magneto-optical spectroscopy testing system according to the target polarization state, wherein the target polarization state includes the polarization angle of the target excitation light corresponding to the excitation light path; Determine a reference angle corresponding to a second linear polarizer disposed in a collection light path of the magneto-optical spectroscopy testing system according to a preset polarization configuration, wherein the preset polarization configuration is used to indicate a relationship between a polarization direction of the target excitation light and a polarization direction of the collection light corresponding to the collection light path; When the magneto-optical spectrum testing system is in different magnetic field strengths, calibrating the first half-wave plate arranged in the excitation optical path according to the reference angle to determine a first mapping relationship between the angle of the first half-wave plate and different magnetic field strengths; When the magneto-optical spectrum testing system is in different magnetic field strengths, the second half-wave plate arranged in the collection light path is calibrated according to the reference angle to determine a second mapping relationship between the angle of the second half-wave plate and different magnetic field strengths; According to the first mapping relationship and the second mapping relationship, a calibration scheme of the magneto-optical spectroscopy testing system under a target magnetic field strength is determined, wherein the calibration scheme is used to indicate the angles of the first half-wave plate and the second half-wave plate when the magneto-optical spectroscopy testing system is under the target magnetic field strength.

2. The method according to claim 1, characterized in that: The step of determining the reference angle corresponding to the second linear polarizer disposed in the light collection path of the magneto-optical spectrum testing system according to the preset polarization configuration includes: In a case where only the first linear polarizer is provided in the excitation light path and only the second linear polarizer is provided in the collection light path, determining a third mapping relationship, wherein the third mapping relationship is used to indicate the intensity of the collected light when the second linear polarizer is at different angles; The reference angle is determined according to the reference light intensity of the collected light under the preset polarization configuration and the third mapping relationship.

3. The method according to claim 2, characterized in that When the magneto-optical spectrum testing system is in different magnetic field strengths, the first half-wave plate arranged in the excitation light path is calibrated according to the reference angle to determine a first mapping relationship between the angle of the first half-wave plate and different magnetic field strengths, including: When the magneto-optical spectrum testing system is in a zero magnetic field intensity, and the excitation light path is provided with the first linear polarizer and the first half-wave plate, and the collection light path is provided with only the second linear polarizer, the second linear polarizer is set at the reference angle, the angle of the first half-wave plate is adjusted until the light intensity of the collected light meets the reference light intensity, and a first initial angle corresponding to the first half-wave plate is determined; When the magneto-optical spectrum testing system is in any non-zero magnetic field intensity, and the excitation light path is provided with the first linear polarizer and the first half-wave plate, and the collection light path is provided with only the second linear polarizer, the second linear polarizer is set at the reference angle, the angle corresponding to the first half-wave plate is adjusted until the light intensity of the collected light meets the reference light intensity, and a first initial adjustment angle corresponding to the first half-wave plate under the magnetic field intensity is determined; The first mapping relationship is determined according to the first initial angle and a first initial adjustment angle corresponding to the first half-wave plate under different magnetic field intensities.

4. The method according to claim 3, characterized in that: The determining the first mapping relationship according to the first initial angle and the first initial adjustment angle corresponding to the first half-wave plate under different magnetic field intensities includes: When the magneto-optical spectrum testing system is in any non-zero magnetic field intensity, and the excitation light path is provided with the first linear polarizer and the first half-wave plate, and the collection light path is provided with the second linear polarizer and the second half-wave plate, half of the first initial adjustment angle corresponding to the first half-wave plate under the magnetic field intensity is determined as the first target adjustment angle corresponding to the first half-wave plate under the magnetic field intensity; The first mapping relationship is determined according to the first initial angle and a first target adjustment angle corresponding to the first half-wave plate under different magnetic field intensities.

5. The method according to claim 2, characterized in that: When the magneto-optical spectrum test system is in different magnetic field strengths, the second half-wave plate arranged in the collection light path is calibrated according to the reference angle to determine a second mapping relationship between the angle of the second half-wave plate and different magnetic field strengths, including: When the magneto-optical spectrum testing system is in a zero magnetic field intensity, and the excitation light path is provided with only the first linear polarizer, and the collection light path is provided with the second linear polarizer and the second half-wave plate, the second linear polarizer is set at the reference angle, the angle of the second half-wave plate is adjusted until the light intensity of the collected light meets the reference light intensity, and a second initial angle corresponding to the second half-wave plate is determined; When the magneto-optical spectroscopy test system is in any non-zero magnetic field intensity, and the excitation light path is provided with only a first linear polarizer, and the collection light path is provided with a second linear polarizer and a second half-wave plate, the second linear polarizer is set at the reference angle, and the angle corresponding to the second half-wave plate is adjusted until the light intensity of the collected light meets the reference light intensity, and a second initial adjustment angle corresponding to the second half-wave plate under the magnetic field intensity is determined; The second mapping relationship is determined according to the second initial angle and the second initial adjustment angle corresponding to the second half-wave plate under different magnetic field intensities.

6. The method according to claim 5, characterized in that The determining the second mapping relationship according to the second initial angle and the second initial adjustment angle corresponding to the second half-wave plate under different magnetic field intensities includes: When the magneto-optical spectrum testing system is in any non-zero magnetic field intensity, and the excitation light path is provided with the first linear polarizer and the first half-wave plate, and the collection light path is provided with the second linear polarizer and the second half-wave plate, 1 / 2 of the second initial adjustment angle corresponding to the second half-wave plate under the magnetic field intensity is determined as the second target adjustment angle corresponding to the second half-wave plate under the magnetic field intensity; The second mapping relationship is determined according to the second initial angle and a second target adjustment angle corresponding to the second half-wave plate under different magnetic field intensities.

7. The method according to any one of claims 2 to 6, characterized in that The intensity of the collected light is determined by a power meter disposed behind the second linear polarizer.

8. The method according to claims 1 to 6, characterized in that The preset polarization configuration includes: the polarization direction corresponding to the target excitation light is parallel to the polarization direction corresponding to the collected light, or the polarization direction corresponding to the target excitation light is perpendicular to the polarization direction corresponding to the collected light.

9. The method according to claims 1 to 6, characterized in that During the calibration process of the second linear polarizer, the first half-wave plate, and the second half-wave plate, the collected light is the reflected signal light of the substrate on which the test object is placed in the magneto-optical spectroscopy test system.

10. A correction device for Faraday rotation effect in magneto-optical spectroscopy, characterized in that: include: A first angle determination module is used to determine the angle corresponding to the first linear polarizer disposed in the excitation light path of the magneto-optical spectroscopy test system according to the target polarization state, wherein the target polarization state includes the polarization angle of the target excitation light corresponding to the excitation light path; A second angle determination module, used to determine a reference angle corresponding to a second linear polarizer disposed in a collection light path of the magneto-optical spectroscopy testing system according to a preset polarization configuration, wherein the preset polarization configuration is used to indicate a relationship between a polarization direction of the target excitation light and a polarization direction of the collection light corresponding to the collection light path; A first mapping determination module is used to calibrate a first half-wave plate provided in the excitation optical path according to the reference angle when the magneto-optical spectroscopy test system is in different magnetic field strengths, and determine a first mapping relationship between the angle of the first half-wave plate and different magnetic field strengths; A second mapping determination module is used to calibrate the second half-wave plate provided in the collection light path according to the reference angle when the magneto-optical spectrum test system is in different magnetic field strengths, and determine a second mapping relationship between the angle of the second half-wave plate and different magnetic field strengths; A calibration scheme determination module is used to determine the calibration scheme of the magneto-optical spectroscopy testing system under the target magnetic field strength according to the first mapping relationship and the second mapping relationship, wherein the calibration scheme is used to indicate the angles of the first half-wave plate and the second half-wave plate when the magneto-optical spectroscopy testing system is under the target magnetic field strength.

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