A method for detecting a magnetic field by using a CrTe / ZnTe half-metal heterojunction grating structure

Abstract

This invention relates to the field of magnetic field detection technology and discloses a magnetic field detection method using a CrTe / ZnTe semi-metallic heterojunction grating structure. The method involves establishing a CrTe / ZnTe semi-metallic heterojunction grating structure through material preparation processes and detector operating frequency bands. A magnetic field is then applied to the CrTe / ZnTe grating structure, establishing a theoretical model that correlates the magnetic field strength with the response spectrum characteristics. The designed structure is fabricated using an etching process, and the sample is then packaged and tested. The invention proposes designing a CrTe / ZnTe semi-metallic heterojunction grating structure and utilizing changes in the response spectrum of the CrTe / ZnTe grating structure to detect the magnitude of the external magnetic field. Even slight changes in the magnetic field can affect the magnetoresistance and other properties of the CrTe / ZnTe material, thereby further altering the resonant frequency of the response spectrum of the CrTe / ZnTe grating structure. This method effectively improves the sensitivity, resonant mechanical properties, and temperature stability of magnetic field detection, providing a novel solution for highly sensitive weak magnetic field detection.

Description

Technical Field

[0001] This invention relates to the field of magnetic field detection technology, specifically to a magnetic field detection method for a CrTe / ZnTe semi-metallic heterojunction grating structure. Background Technology

[0002] The scope of magnetic measurement extends far beyond the testing of magnetic materials or the measurement of magnetic fields. Its practical applications are diverse and multi-faceted. By directly or indirectly measuring electrical magnetic parameters such as magnetic field strength H, magnetic flux density B, permeability μ, magnetization coefficient X, and magnetostriction coefficient λ using scientific methods, it provides new technical means for applications such as paleomagnetism, magnetoarchaeology, mine exploration, displacement or distance detection, current detection, non-destructive testing of materials, and medical diagnosis. In some applications, it is necessary to collect weak electromagnetic information, such as weak current measurement, pH value, castor oil concentration, or even the presence of Salmonella. However, existing fluxgate magnetometers, giant magnetoresistance sensors, and fiber optic magnetic sensors suffer from insufficient sensitivity and accuracy when dealing with weak magnetic field parameters. Recent studies have proposed using materials such as CaSi2, Co / Cu, Cr / FeMn, MgxO, Al2O3, and graphene as intermediate magnetoresistive layers to design miniaturized magnetic sensors. Both the anomalous magnetoresistive effect and the Hall effect enable the measurement of weak magnetic fields to a certain extent at room temperature. However, achieving highly sensitive weak magnetic field detection with such sensors still faces significant challenges. To effectively improve the stability, size, and magnetoresistive sensitivity of existing weak magnetic field sensors, this invention proposes a grating structure magnetic field detector fabricated using CrTe / ZnTe semi-metallic heterojunction material. Summary of the Invention

[0003] (a) Technical problems to be solved

[0004] To address the problem of low sensitivity and accuracy of existing magnetic field sensing devices in weak magnetic field applications, this invention provides a magnetic field detection method using a CrTe / ZnTe semi-metallic heterojunction grating structure. When there is a small change in the external magnetic field, the CrTe / ZnTe material component in the grating unit can change its own magnetoresistance, thereby changing the response spectrum of the CrTe / ZnTe grating structure. The change in the response spectrum pattern ultimately reflects the slight change and magnitude of the magnetic field.

[0005] (II) Technical Solution

[0006] To achieve the above objectives, the present invention provides the following technical solution: a magnetic field detection method for a CrTe / ZnTe semi-metallic heterojunction grating structure. The method involves establishing a CrTe / ZnTe semi-metallic heterojunction grating structure through material preparation processes and detector operating frequency bands. Subsequently, a magnetic field is applied to the CrTe / ZnTe grating structure, and numerical simulation software is used to calculate the changes in the magnetoresistance characteristics of the CrTe / ZnTe material under different magnetic field intensities, i.e., whether it exhibits metallic, semiconductor, or insulating properties, thereby reflecting the changes in the grating structure's response spectrum. A theoretical model is established that corresponds between magnetic field intensity and response spectrum characteristics.

[0007] After the CrTe / ZnTe grating structure is designed, the designed structure is processed using an etching process, and then the sample is packaged and tested.

[0008] Preferably, the grating structure parameters, such as period, gap width, and thickness, can be determined by theoretical formulas and numerical simulation calculations based on the designed resonant frequency.

[0009] Preferably, for CrTe / ZnTe materials n eff =28%, c=3.0*10^8m / s.

[0010] Preferably, the CrTe / ZnTe grating basic unit is composed of a dielectric layer and an electromagnetic induction layer. The dielectric layer material can be polytetrafluoroethylene, the magnetic induction layer is selected as CrTe / ZnTe semi-metallic heterojunction material, the resonant frequency range is selected as 1GHz-9.4GHz, the unit structure thickness is 1mm, and the thickness of the CrTe / ZnTe layer is 100μm.

[0011] Preferably, the specific parameters of the periodic grating structure can be obtained by using theoretical formulas and numerical simulation calculations, namely, the grating period p is 1071 μm and the gap width g is 321.3 μm.

[0012] Preferably, when a magnetic field is applied to the CrTe / ZnTe grating structure, the magnetoresistance characteristics of the CrTe / ZnTe material will change, thereby affecting the resonant frequency of the structure's response spectrum. The intensity of the ambient magnetic field can be detected by monitoring the changes in the response spectrum of the CrTe / ZnTe grating structure.

[0013] (III) Beneficial Effects

[0014] Compared with the prior art, the present invention provides a magnetic field detection method for a CrTe / ZnTe semi-metallic heterojunction grating structure, which has the following advantages:

[0015] 1. A magnetic field detection method using a CrTe / ZnTe semi-metallic heterojunction grating structure is proposed. The method involves designing a CrTe / ZnTe semi-metallic heterojunction grating structure and utilizing changes in the response spectrum of the CrTe / ZnTe grating structure to detect the magnitude of an external magnetic field. Since even slight changes in the magnetic field affect the magnetoresistance and other properties of the CrTe / ZnTe material, they further alter the resonant frequency of the CrTe / ZnTe grating structure's response spectrum. This method effectively improves the sensitivity, resonant mechanical properties, and temperature stability of magnetic field detection, providing a novel solution for highly sensitive weak magnetic field detection.

[0016] 2. A magnetic field detection method for a CrTe / ZnTe semi-metallic heterojunction grating structure is proposed and designed. When an external magnetic field is applied to the structure, it changes the internal magnetic permeability of the CrTe / ZnTe material, thereby altering the spectral resonant frequency of the grating unit and further affecting the overall response spectrum of the CrTe / ZnTe grating structure. By utilizing the physical relationship between magnetic field strength and response spectrum characteristics, changes in the magnetic field can be efficiently measured indirectly through variations in the response spectrum. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the grating structure based on the CrTe / ZnTe magnetic induction unit of the present invention. Detailed Implementation

[0018] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] Please see Figure 1This invention discloses a magnetic field detection method for a CrTe / ZnTe semi-metallic heterojunction grating structure. CrTe / ZnTe is a novel type of semi-metallic ferromagnetic material with a band structure exhibiting metallicity in one spin direction and semiconductor or insulatingness in the other, resulting in complete (100%) spin polarization of conduction electrons near the Fermi level. Therefore, CrTe / ZnTe is highly suitable as a spin-polarized electron injection source for semiconductors, significantly improving the performance of spintronic devices, such as spin diode effect, rectification rate, and tunneling magnetoresistance. The proposed CrTe / ZnTe grating structure, under the influence of a weak external magnetic field, spontaneously adjusts the magnetoresistance of the CrTe / ZnTe material, thereby affecting the resonant frequency point of the designed grating structure's response spectrum. The resonant wave spectrum corresponds to the range of magnetic field values. Furthermore, the CrTe / ZnTe material exhibits a large half-metallic gap (up to 0.88 eV), resulting in highly active metallic properties and excellent mechanical properties, with minimal influence from defects or temperature. In summary, the response spectrum of the CrTe / ZnTe grating structure is highly sensitive to material characteristics, demonstrating strong resistance to temperature interference and mechanical frequency attenuation. Even minute changes in the magnetic field can affect the structure's response spectrum; therefore, this method effectively improves the sensitivity of weak magnetic field detection.

[0020] The resonant frequency range of the CrTe / ZnTe grating structure can be determined by the material fabrication process and the detector's operating frequency band. The corresponding grating structure parameters, such as period, gap width, and thickness, can be determined using theoretical formulas and numerical simulations based on the designed resonant frequency. The grating period and resonant frequency satisfy the formula p = c / (n eff The relationship described in ×f0) is where p is the period, c is the speed of light, and n is the speed of light. eff The effective refractive index of the grating structure; where, for CrTe / ZnTe material, n eff =28%, c = 3.0 * 10^8 m / s. Subsequently, a magnetic field was applied to the CrTe / ZnTe grating structure, and numerical simulation software was used to calculate the changes in the magnetoresistance characteristics of the CrTe / ZnTe material under different magnetic field strengths, i.e., whether it exhibits metallic, semiconductor, or insulating properties, thus reflecting the changes in the grating structure's response spectrum. A theoretical model corresponding to the magnetic field strength and response spectrum characteristics was established. After designing the CrTe / ZnTe grating structure, the designed structure was fabricated using an etching process. Then, the sample was packaged and tested.

[0021] It consists of a dielectric layer and an electromagnetic induction layer, such as Figure 1The CrTe / ZnTe grating basic unit shown can be made of polytetrafluoroethylene (PTFE) as the dielectric layer and CrTe / ZnTe semi-metallic heterojunction material as the magnetic induction layer. The resonant frequency range is selected as 1 GHz-9.4 GHz, the unit structure thickness is 1 mm, and the CrTe / ZnTe layer thickness is 100 μm. Using theoretical formulas and numerical simulations, a shape like... Figure 1 The specific parameters of the periodic grating structure shown are: a grating period p of 1071 μm and a gap width g of 321.3 μm. When a magnetic field is applied to the CrTe / ZnTe grating structure, the magnetoresistance properties of the CrTe / ZnTe material will change, thus affecting the resonant frequency of the structure's response spectrum. Therefore, the strength of the ambient magnetic field can be detected by monitoring the changes in the response spectrum of the CrTe / ZnTe grating structure.

[0022] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method for detecting the magnetic field of a CrTe / ZnTe half-metal heterojunction grating structure, characterized in that: The CrTe / ZnTe semi-metallic heterojunction grating structure was established by using material preparation processes and operating frequency bands. Subsequently, a magnetic field was applied to the CrTe / ZnTe grating structure, and numerical simulation software was used to calculate the changes in magnetoresistance characteristics of the CrTe / ZnTe material under different magnetic field intensities, i.e., whether it exhibits metallic, semiconductor, or insulating properties, thereby reflecting the changes in the response spectrum of the grating structure. A theoretical model was established that corresponds between magnetic field intensity and response spectrum characteristics. After the CrTe / ZnTe grating structure is designed, the designed structure is processed by etching process to obtain a CrTe / ZnTe semi-metallic heterojunction grating structure sample; The sample was sealed to avoid interference from the external environment. Then, the sealed sample was placed in a test environment with a known magnetic field strength. By monitoring the changes in its response spectrum, the correspondence between the magnetic field strength and the response spectrum characteristics was verified, and the sample sealing test was completed. When a magnetic field is applied to a CrTe / ZnTe grating structure, the magnetoresistance properties of the CrTe / ZnTe material will change, thereby affecting the resonant frequency of the structure's response spectrum. The strength of the ambient magnetic field can be detected by monitoring the changes in the response spectrum of the CrTe / ZnTe grating structure.

2. The magnetic field detection method for a CrTe / ZnTe semi-metallic heterojunction grating structure according to claim 1, characterized in that: The core parameters of the grating structure include period, gap width, and thickness. These parameters can be determined by theoretical formulas and numerical simulation calculations based on the designed resonant frequency.

3. The magnetic field detection method for a CrTe / ZnTe half-metal heterojunction grating structure according to claim 1, characterized in that: in, For the CrTe / ZnTe material, neff = 28% and c = 3.

0. 10^8 m / s.

4. The magnetic field detection method for a CrTe / ZnTe semi-metallic heterojunction grating structure according to claim 1, characterized in that: The basic unit of the CrTe / ZnTe grating structure consists of a dielectric layer and an electromagnetic induction layer. The dielectric layer is made of polytetrafluoroethylene, and the electromagnetic induction layer is made of CrTe / ZnTe semi-metallic heterojunction material. The resonant frequency range is selected as 1GHz-9.4GHz, the unit structure thickness is 1mm, and the thickness of the CrTe / ZnTe layer is 100μm.

5. The magnetic field detection method for a CrTe / ZnTe semi-metallic heterojunction grating structure according to claim 1, characterized in that: The specific parameters of the periodic grating structure can be obtained by using theoretical formulas and numerical simulation calculations, namely, the grating period p is 1071 μm and the gap width g is 321.3 μm.

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