Spin filter based on st-fmr

Abstract

The utility model provides a kind of spin filter based on ST-FMR.The spin filter based on ST-FMR includes: spin torque ferromagnetic resonance device, including ferromagnetic material layer, heavy metal material layer and electrode structure, the spin torque ferromagnetic resonance is formed between the ferromagnetic material layer and the heavy metal material layer, the electrode structure is connected with ferromagnetic material layer, heavy metal material layer;Radio frequency signal input module is used to pass into spin torque ferromagnetic resonance device with different frequency radio frequency signal;Wherein, spin torque ferromagnetic resonance device will generate voltage signal after receiving radio frequency signal;Direct current adjusting module is used to deliver different size direct current to the spin torque ferromagnetic resonance device;Wherein, the half-width of voltage signal outputted by spin torque ferromagnetic resonance device will be different after receiving different size direct current;Signal transmission and processing module is used to obtain the voltage signal outputted by spin torque ferromagnetic resonance device.

Description

Technical Field

[0001] This invention belongs to the field of signal processing technology, and particularly relates to a spin filter based on ST-FMR. Background Technology

[0002] In the era of big data, feature extraction is a crucial step in data processing and analysis. Its core lies in extracting meaningful features from raw data to improve the efficiency and accuracy of machine learning and data analysis. First, feature extraction simplifies high-dimensional data through dimensionality reduction, which not only reduces computational complexity but also improves model speed and performance. Second, feature extraction helps filter noise, remove redundant information, and extract the most relevant and valuable features, thereby enhancing the robustness and accuracy of the model.

[0003] Effective feature extraction is crucial for improving model performance. High-quality features enable models to more accurately capture patterns and regularities in data, improving prediction and classification accuracy. Furthermore, feature extraction transforms complex, high-dimensional data into easily understandable and interpretable low-dimensional data, facilitating data visualization and enabling data scientists and business analysts to better understand data and discover hidden patterns and trends. Simultaneously, reducing data dimensionality through feature extraction can significantly lower data storage costs. In practical applications, feature extraction plays a vital role. For example, in image processing, feature extraction is used to extract information such as edges, textures, and colors from images for image classification and object detection. In natural language processing, feature extraction is used to extract keywords and topics from text for text classification and sentiment analysis. In financial data analysis, feature extraction helps extract useful information from data such as stock prices and trading volumes for market forecasting and risk management.

[0004] However, traditional feature extraction methods mainly rely on spectrum analyzers and filter banks. These devices are not only bulky and slow in response, but more importantly, the feature accuracy is difficult to adjust because the filtering bandwidth is not adjustable. Utility Model Content

[0005] This invention provides a spin filter based on ST-FMR, which has an adjustable filtering bandwidth, thereby allowing selective adjustment of the precision of the characteristics.

[0006] This application provides a spin filter based on ST-FMR, comprising: A spin-torque ferromagnetic resonance device includes a ferromagnetic material layer, a heavy metal material layer, and an electrode structure. A spin-torque ferromagnetic resonance is formed between the ferromagnetic material layer and the heavy metal layer. The electrode structure is connected to the ferromagnetic material layer and the heavy metal layer. The radio frequency signal input module is used to pass radio frequency signals of different frequencies into the spin torque ferromagnetic resonance device; wherein, after receiving the radio frequency signal, the spin torque ferromagnetic resonance device generates a voltage signal; A DC current regulation module is used to supply DC current of different magnitudes to the spin torque ferromagnetic resonance device; wherein, after receiving DC current of different magnitudes, the full width at half maximum (FWHM) of the output voltage signal of the spin torque ferromagnetic resonance device will be different. The signal transmission and processing module is used to acquire the voltage signal output by the spin torque ferromagnetic resonance device.

[0007] Optionally, when the DC current adjustment module supplies a positive DC current to the spin torque ferromagnetic resonance device, the filtering bandwidth of the spin torque ferromagnetic resonance device increases; when the DC current adjustment module supplies a negative DC current to the spin torque ferromagnetic resonance device, the filtering bandwidth of the spin torque ferromagnetic resonance device decreases.

[0008] Optionally, the ferromagnetic material layer is a yttrium iron garnet layer or a permalloy layer.

[0009] Optionally, the heavy metal material layer is a Pt layer.

[0010] Optionally, the thickness of the heavy metal material layer is 5~10 nm.

[0011] Optionally, the thickness of the ferromagnetic material layer is 10~100nm.

[0012] Optionally, the electrode structure is disposed on the side of the ferromagnetic material layer and the heavy metal material layer, and the electrode structure and the stacked ferromagnetic material layer and the heavy metal material layer form an E-shaped structure or a Hall stripe structure.

[0013] Optionally, the signal transmission and processing module is a voltmeter or a phase-locked loop (PLL).

[0014] Optionally, the radio frequency signal input module is an arbitrary waveform generator.

[0015] Optionally, the DC current regulation module is a DC current source.

[0016] The beneficial effects of the technical solutions provided in this disclosure are: This disclosure provides a spin filter based on ST-FMR, which includes a spin-torque ferromagnetic resonance (ST-FMR) device. The ST-FMR device drives ferromagnetic resonance through spin torque induced by alternating current. When the signal to be processed is transmitted to the ST-FMR device in the form of alternating current, non-uniform spins are generated and accumulated at the interface between the ferromagnetic and heavy metal material layers due to the strong spin-orbit coupling of the heavy metal material layer. These spins diffuse into the ferromagnetic material layer, thereby exerting a torque on the magnetic moment of the ferromagnetic material layer. Since the injected charge flow is oscillating, the torque induced by the alternating current is also oscillating, causing Larmor precession of the magnetic moment of the ferromagnetic material layer near the effective magnetic field of the ferromagnetic material layer. Larmor precession ultimately generates a DC voltage in the device, which can be detected by a voltmeter or a phase-locked loop (PLL). More specifically, in a spin-torque ferromagnetic resonance (ST-FMR) device, the coupling of oscillating magnetoresistance and microwave current (i.e., the input signal to be processed) generates a DC voltage that can be measured by a DC voltmeter or a phase-locked loop (PLL). The device also includes a DC current regulation module, which applies an additional DC current to the ST-FMR device when signal processing is required. When the input DC current is positive, for example, when the angle between the DC current direction and the magnetic field direction of the ferromagnetic material layer is acute (e.g., 45°), the DC current, with its polarization direction parallel to the magnetization direction, is injected into the ferromagnetic material layer. The resulting spin magnetic moment enhances magnetic relaxation, which in turn increases the linewidth of the ST-FMR. Conversely, when the injected DC current is in a negative direction, for example, when the angle between the direction of the DC current and the magnetic field direction of the ferromagnetic material layer is obtuse (e.g., 225°), due to the symmetry of the spin Hall angle effect, the polarization direction of the injected spin current is parallel to but opposite to the magnetization direction, which weakens the magnetic relaxation of the spin-torque ferromagnetic resonance device, thereby reducing the linewidth of the spin-torque ferromagnetic resonance device. By injecting an additional DC current into the spin-torque ferromagnetic resonance device, the signal to be processed input to the spin-torque ferromagnetic resonance device can be processed. By controlling the magnitude or direction of the injected DC current, feature extraction can be performed on the signal to be processed to obtain a signal that meets the requirements. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0018] Figure 1A schematic diagram of a spin filter based on ST-FMR provided for an embodiment of this disclosure; Figure 2 A schematic diagram of another spin filter based on ST-FMR provided in this embodiment of the present disclosure; Figure 3 A flowchart illustrating a method for using a spin filter based on ST-FMR, provided in this embodiment of the disclosure; Figure 4 A performance diagram of an ST-FMR device provided in an embodiment of this disclosure; Figure 5 A waveform diagram of the input signal of an ST-FMR device provided in an embodiment of this disclosure; Figure 6 Performance diagram of another ST-FMR device provided in this disclosure embodiment; Figure 7 A waveform diagram of the output signal of an ST-FMR device provided in an embodiment of this disclosure; Figure 8 Performance diagram of another ST-FMR device provided in this disclosure embodiment; Figure 9 A waveform diagram of the input signal of another ST-FMR device provided in an embodiment of this disclosure; Figure 10 A waveform diagram of the output signal of another ST-FMR device provided in an embodiment of this disclosure; Figure 11 Performance diagram of another ST-FMR device provided in this disclosure embodiment; Figure 12 A waveform diagram of the output signal of another ST-FMR device provided in an embodiment of this disclosure; Figure 13 Performance diagram of another ST-FMR device provided in this disclosure embodiment; Figure 14 Performance diagram of another ST-FMR device provided in this disclosure embodiment; Figure 15 Performance diagram of another ST-FMR device provided in this disclosure embodiment; Figure 16 A graph showing the output signal of another ST-FMR device provided in an embodiment of this disclosure.

[0019] The attached figures are labeled as follows: 1: ST-FMR device; 11: Ferromagnetic material layer; 12: Heavy metal material layer; 13: Electrode structure; 2: Radio frequency signal input module; 3: Signal transmission and processing module; 4: DC current regulation module. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of this utility model clearer, the technical solutions of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0021] This paper proposes a novel spin filter based on ST-FMR, utilizing spintronics. This device significantly reduces area footprint, and its inherent Fast Fourier Transform (FFT) capability greatly accelerates response time. Furthermore, the adjustable filter bandwidth allows for flexible adjustment of feature extraction accuracy based on specific needs. This innovation is significant in the field of feature extraction, providing a more efficient and flexible solution for big data analytics and intelligent applications. The application of this novel spintronic device will usher in new development opportunities for feature extraction technology, providing stronger technical support for intelligent and data-driven decision-making across various industries.

[0022] Figure 1 This is a schematic diagram of a spin filter based on ST-FMR provided in an embodiment of this disclosure. Wherein, Figure 1 This is a top view of a spin filter based on ST-FMR.

[0023] Figure 2 A schematic diagram of another spin filter based on ST-FMR provided in this disclosure embodiment. Wherein, Figure 2 For ST-FMR based spin filter edge Figure 1 Cross-sectional view of dashed line AA'.

[0024] See also Figure 1 and Figure 2 The device includes: A spin torque ferromagnetic resonance device 1 includes a ferromagnetic material layer 11, a heavy metal material layer 12, and an electrode structure 13. A spin torque ferromagnetic resonance is formed between the ferromagnetic material layer 11 and the heavy metal material layer 12. The electrode structure 13 is connected to the ferromagnetic material layer 11 and the heavy metal material layer 12. The radio frequency signal input module 2 is used to input radio frequency signals of different frequencies into the spin torque ferromagnetic resonance device; wherein, after receiving the radio frequency signal, the spin torque ferromagnetic resonance device generates a voltage signal; Signal transmission and processing module 3 is used to acquire the voltage signal output by the spin torque ferromagnetic resonance device; The DC current adjustment module 4 is used to supply different magnitudes of DC current to the spin torque ferromagnetic resonance device; wherein, after receiving different magnitudes of DC current, the full width at half maximum (FWHM) of the output voltage signal of the spin torque ferromagnetic resonance device will be different.

[0025] In this embodiment, a spin filter based on ST-FMR is provided. The device includes a spin-torque ferromagnetic resonance (ST-FMR) device, which drives ferromagnetic resonance through spin torque induced by alternating current. When the signal to be processed is transmitted to the ST-FMR device in the form of alternating current, non-uniform spins are generated and accumulated at the interface between the ferromagnetic and heavy metal material layers due to the strong spin-orbit coupling of the heavy metal material layer. These spins diffuse into the ferromagnetic material layer, thereby exerting a torque on the magnetic moment of the ferromagnetic material layer. Since the injected charge flow is oscillating, the torque induced by the alternating current is also oscillating, causing Larmor precession of the magnetic moment of the ferromagnetic material layer near the effective magnetic field of the ferromagnetic material layer. Larmor precession ultimately generates a DC voltage in the device, which can be detected by a voltmeter or a phase-locked amplifier. More specifically, in the ST-FMR device, the coupling of oscillating magnetoresistance and microwave current generates a DC voltage that can be measured by a DC voltmeter or a lock-in amplifier. The device also includes a DC current regulation module. When signal processing is required, an additional current is applied to the spin-torque ferromagnetic resonance device (ST-FMR) via this module. When the input DC current is positive, for example, when the angle between the DC current direction and the magnetic field direction of the ferromagnetic material layer is acute (e.g., 45°), the DC current, with its polarization direction parallel to the magnetization direction, is injected into the ferromagnetic material layer. The resulting spin magnetic moment enhances magnetic relaxation, which in turn increases the linewidth of the ST-FMR. Conversely, when the injected DC current is negative, for example, when the angle between the DC current direction and the magnetic field direction of the ferromagnetic material layer is obtuse (e.g., 225°), due to the symmetry of the spin Hall angle effect, the polarization direction of the injected spin current is parallel to but opposite to the magnetization direction. This weakens the magnetic relaxation of the ST-Torque ferromagnetic resonance device, thereby reducing its linewidth. By injecting an additional DC current into the spin torque ferromagnetic resonance device, the signal to be processed input to the spin torque ferromagnetic resonance device can be processed. By adjusting the magnitude or direction of the injected DC current, feature extraction can be performed on the signal to be processed, and a signal that meets the requirements can be obtained.

[0026] In one example provided in this disclosure, the signal to be processed can be an audio signal. Of course, the above-described single signal to be processed is only one example, and the signal to be processed can also be other signals.

[0027] In this embodiment of the disclosure, when the DC current adjustment module supplies a positive DC current to the spin torque ferromagnetic resonance device, the filtering bandwidth of the spin torque ferromagnetic resonance device increases; when the DC current adjustment module supplies a negative DC current to the spin torque ferromagnetic resonance device, the filtering bandwidth of the spin torque ferromagnetic resonance device decreases.

[0028] In this embodiment of the disclosure, by supplying DC current in different directions to the spin torque ferromagnetic resonance device, the filtering bandwidth of the spin torque ferromagnetic resonance device can be increased or decreased. The magnitude of the DC current can affect the degree to which the filtering bandwidth is increased or decreased, thereby forming a spin filter based on ST-FMR with adjustable filtering bandwidth.

[0029] In this context, the direction of the positive direct current refers to an acute angle between the direction of the direct current and the direction of the magnetic field of the ferromagnetic material layer in the spin-torque ferromagnetic resonance device. The direction of the negative direct current refers to an obtuse angle between the direction of the direct current and the direction of the magnetic field of the ferromagnetic material layer in the spin-torque ferromagnetic resonance device.

[0030] In this embodiment, the ferromagnetic material layer 11 is formed of yttrium iron garnet or permalloy. When yttrium iron garnet is used as the ferromagnetic material layer, its low drag coefficient is beneficial for the signal modulation effect of the subsequent input DC current, making the DC current's modulation effect on the spin torque ferromagnetic resonance device more significant. Using permalloy results in a higher signal intensity output by the spin torque ferromagnetic resonance device.

[0031] In this embodiment, the heavy metal material layer is formed using Pt. Pt has a relatively large spin Hall angle, and using Pt as the heavy metal material layer is more conducive to forming a strong spin-orbit coupling effect, resulting in a spin-torque ferromagnetic resonance device with better performance.

[0032] In this embodiment of the disclosure, the thickness of the heavy metal material layer is 5~10nm.

[0033] For example, the thickness of the heavy metal material layer is 8 nm.

[0034] In this embodiment, the thickness of the heavy metal material layer should not be too thick or too thin. When acquiring the output signal (DC voltage) of the spin-torque ferromagnetic resonance device, the signal will be measured on the surface of the heavy metal material layer. If the heavy metal material layer is too thick, it will hinder the signal from passing through it. If the heavy metal material layer is too thin, the spin-orbit coupling effect of the heavy metal material layer will be poor, which is detrimental to the performance of the spin-torque ferromagnetic resonance device.

[0035] In this embodiment of the disclosure, the thickness of the ferromagnetic material layer is 10~100nm.

[0036] For example, the thickness of the ferromagnetic material layer is 18 nm.

[0037] In this embodiment, the thickness of the ferromagnetic material layer should not be too thick. Too thick a layer is not conducive to the size of the device and also to the manufacturing cost. Too thin a layer will result in a weak signal generated by the ST-FMR device.

[0038] In this embodiment of the present disclosure, the electrode structure 13 is disposed on the side of the ferromagnetic material layer 11 and the heavy metal material layer 12, and the electrode structure 13 and the stacked ferromagnetic material layer 11 and the heavy metal material layer 12 form an E-shaped structure or a Hall stripe structure.

[0039] In the embodiments disclosed herein, an E-shaped structure or a Hall stripe structure can be used to obtain a larger spin-orbit torque and a larger current density, thereby enhancing the signal of the ST-FMR device.

[0040] In this embodiment of the disclosure, the signal transmission and processing module 2 is a voltmeter or a phase-locked loop.

[0041] In this embodiment of the disclosure, the signal output by the ST-FMR device can be accurately obtained using a voltmeter or a phase-locked loop.

[0042] In this embodiment of the disclosure, Figure 1 The dimensions of the middle electrode are as follows: Width portion: D1 is 29.71nm, D2 is 217nm, D3 is 150nm, D4 is 524nm, D5 is 100nm, and D6 is 50nm.

[0043] Length and spacing: L1 is 296 nm, L2 is 40.8 nm, L3 is 481 nm, and L4 is 400.7 nm.

[0044] The included angle is α = 135° and β = 145.6°.

[0045] By adjusting the size parameters of the electrodes, the frequency range of microwave current that the ST-FMR device can pass through can be controlled. At the same time, impedance matching of the ST-FMR can be ensured, thereby ensuring good performance of the ST-FMR device. The above parameters are an example provided by the embodiments of this disclosure. The actual size of the ST-FMR device can be set as needed.

[0046] In one example provided in this disclosure, the radio frequency signal input module 2 can be an arbitrary waveform generator, the signal transmission and processing module 3 can be a voltmeter, and the DC current regulation module 4 can be a DC current source.

[0047] Figure 3A flowchart illustrating a method for using a spin filter based on ST-FMR, as provided in this disclosure embodiment. See also... Figure 3 The method includes the following steps: S101, Input the signal to be processed into the spin torque ferromagnetic resonance device.

[0048] The signal to be processed is input into the ST-FMR device in the form of a radio frequency signal.

[0049] S102, Obtain the signal output by the spin torque ferromagnetic resonance device.

[0050] The ST-FMR curve is generated by acquiring the voltage signal output by the ST-FMR device through a voltmeter or phase-locked loop.

[0051] The formula for testing the ST-FMR curve is as follows:

[0052] Among them, V A and V S These are the intensities of antisymmetric and symmetric linear forms, respectively. H and H0 are the filter linewidth and resonant peak position of the ST-FMR signal, respectively. This allows us to obtain the resonant peak position and linewidth at the test frequency. Combining these parameters, we can obtain the ST-FMR curve shape for any frequency RF signal.

[0053] S103. When the signal output by the spin torque ferromagnetic resonance device does not meet the requirements, a direct current is supplied to the spin torque ferromagnetic resonance device to enhance or weaken the magnetic relaxation of the spin torque ferromagnetic resonance device, so as to regulate the signal output by the spin torque ferromagnetic resonance device.

[0054] In step S103, when the accuracy of the signal output by the spin torque ferromagnetic resonance device does not meet the requirements, a reverse DC current is supplied to the spin torque ferromagnetic resonance device; or, when the noise of the signal output by the spin torque ferromagnetic resonance device does not meet the requirements, a forward DC current is supplied to the spin torque ferromagnetic resonance device.

[0055] By identifying a specific aspect of the signal's performance that is important in feature extraction, determining the direction of the input DC current, and adjusting the magnitude of the DC current, a signal that meets the requirements can be obtained.

[0056] In this embodiment, a feature extraction method is also provided. By inputting a DC current into an ST-FMR device, the magnetic relaxation of the ST-FMR device is controlled to regulate the signal output by the ST-FMR device, thereby obtaining a signal that meets the requirements. Simultaneously, by inputting DC currents of different directions and magnitudes, a spin filter based on ST-FMR with adjustable filtering bandwidth can be obtained. By adjusting the filtering bandwidth of the ST-FMR device, the waveform of the signal output by the ST-FMR device can be controlled.

[0057] Figure 4 Performance diagram of an ST-FMR device provided in an embodiment of this disclosure. See also Figure 4 , Figure 4 The horizontal axis represents the magnitude of the magnetic field of the ST-FMR device, and the vertical axis represents the measured signal output by the ST-FMR.

[0058] The performance of the ST-FMR device was measured using a single-frequency radio frequency signal, such as... Figure 4 The performance of the ST-FMR device was measured using signals at 8 GHz, 8.5 GHz, 9 GHz, 9.5 GHz and 10 GHz, resulting in five performance curves.

[0059] Figure 5 A waveform diagram of the input signal of an ST-FMR device provided in an embodiment of this disclosure. See also... Figure 5 The input signal is a 5.0 GHz radio frequency signal.

[0060] Figure 6 Performance diagram of another ST-FMR device provided in an embodiment of this disclosure. Figure 6 It is based on Figure 4 The actual measured performance parameters of the ST-FMR device are used to simulate the filtering performance of the ST-FMR device in the simulation software.

[0061] Figure 7 A waveform diagram of the output signal of an ST-FMR device provided in an embodiment of this disclosure. See also... Figure 5 , Figure 6 and Figure 7 ,when Figure 5 The input signal in the middle passes through Figure 6 After processing the ST-FMR device, the following was obtained: Figure 7 The waveform of the output signal in the process.

[0062] exist Figure 7 In this process, the waveform of the output signal consists of point values. By performing a dot product operation on these point values, multiple points are fitted into an output curve.

[0063] Figure 8Performance diagram of another ST-FMR device provided in an embodiment of this disclosure. See also Figure 8 ,exist Figure 8 The diagram illustrates the relationship between the filter linewidth of the ST-FMR device and the direction of the input DC current. The angle φ between the direction of the DC current input to the ST-FMR device and the direction of the internal magnetic field of the ST-FMR device is also shown. H At 45°, the filter linewidth of the ST-FMR device ( H W ) and the input DC current (I dc The magnitude of the angle φ between the direction of the DC current input to the ST-FMR device and the direction of the internal magnetic field of the ST-FMR device is negatively correlated. H At 225°, the filter linewidth of the ST-FMR device is related to the input DC current (I0). dc The magnitudes of ) are positively correlated.

[0064] Figure 8 In the text, YIG indicates that the ferromagnetic material layer in the ST-FMR device is made of yttrium iron garnet, and Pt indicates that the heavy metal material layer is made of Pt.

[0065] Figure 9 A waveform diagram of the input signal of another ST-FMR device provided in an embodiment of this disclosure. See also... Figure 9 ,exist Figure 9 It provides a waveform for a complex input signal.

[0066] Figure 10 A waveform diagram of the output signal of another ST-FMR device provided in an embodiment of this disclosure. See also... Figure 10 , Figure 9 The input signal in the middle passes through Figure 6 After processing, the ST-FMR device in the middle is obtained Figure 10 The output signal in.

[0067] Figure 11 Performance diagram of another ST-FMR device provided in an embodiment of this disclosure. See also Figure 11 , Figure 1 for Figure 6 A partially enlarged view of the performance curves of the ST-FMR device. The DC current I is shown below. dc The size is 0mA.

[0068] Figure 12 A waveform diagram of the output signal of another ST-FMR device provided in an embodiment of this disclosure. See also... Figure 12 ,right Figure 10 After performing a dot product on the output signal, the fitted curve is... Figure 12 The curve in the image.

[0069] Figure 13 Performance diagram of another ST-FMR device provided in an embodiment of this disclosure. See also Figure 13 ,exist Figure 11 Based on this, by inputting a positive 3mA DC current into the ST-FMR device, the filtering bandwidth of the ST-FMR device increases.

[0070] Figure 14 Performance diagram of another ST-FMR device provided in an embodiment of this disclosure. See also Figure 14 , Figure 9 The input signal in the middle passes through Figure 13 After processing the ST-FMR device, the following is obtained: Figure 14 The output signal.

[0071] Figure 14 and Figure 12 The waveforms of the input signals are different, the difference lies in Figure 14 A 3mA DC current was input into the ST-FMR device, which changed the filtering bandwidth of the ST-FMR device, thus resulting in a different waveform of the signal output by the ST-FMR device.

[0072] Figure 15 Performance diagram of another ST-FMR device provided in an embodiment of this disclosure. See also Figure 15 When a reverse 3mA DC current is input into the ST-FMR device, the filter linewidth of the ST-FMR device decreases.

[0073] Figure 16 A graph showing the output signal of another ST-FMR device provided in an embodiment of this disclosure. See also... Figure 16 , Figure 16 and Figure 12 , Figure 14 The waveforms of the output curves in each are different; the difference lies in... Figure 16 A reverse 3mA DC current was input into the ST-FMR device, reducing the filter linewidth of the ST-FMR device.

[0074] It is worth noting that, Figure 12 , Figure 14 and Figure 16 The input signals are all Figure 9 The signal in.

[0075] It is worth noting that, Figures 10 to 16 The attached figure shows the simulation results.

[0076] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and not to limit it. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this utility model.

Claims

1. A spin filter based on ST-FMR, characterized in that, include: A spin-torque ferromagnetic resonance device includes a ferromagnetic material layer, a heavy metal material layer, and an electrode structure. A spin-torque ferromagnetic resonance is formed between the ferromagnetic material layer and the heavy metal layer. The electrode structure is connected to the ferromagnetic material layer and the heavy metal layer. The radio frequency signal input module is used to pass radio frequency signals of different frequencies into the spin torque ferromagnetic resonance device; wherein, after receiving the radio frequency signal, the spin torque ferromagnetic resonance device generates a voltage signal; A DC current regulation module is used to supply DC current of different magnitudes to the spin torque ferromagnetic resonance device; wherein, after receiving DC current of different magnitudes, the full width at half maximum (FWHM) of the output voltage signal of the spin torque ferromagnetic resonance device will be different. The signal transmission and processing module is used to acquire the voltage signal output by the spin torque ferromagnetic resonance device.

2. The spin filter based on ST-FMR according to claim 1, characterized in that, When the DC current regulation module supplies a positive DC current to the spin torque ferromagnetic resonance device, the filtering bandwidth of the spin torque ferromagnetic resonance device increases; when the DC current regulation module supplies a negative DC current to the spin torque ferromagnetic resonance device, the filtering bandwidth of the spin torque ferromagnetic resonance device decreases.

3. The spin filter based on ST-FMR according to claim 1, characterized in that, The ferromagnetic material layer is a yttrium iron garnet layer or a permalloy layer.

4. The spin filter based on ST-FMR according to claim 1, characterized in that, The heavy metal material layer is a Pt layer.

5. The spin filter based on ST-FMR according to claim 1, characterized in that, The thickness of the heavy metal material layer is 5~10nm.

6. The spin filter based on ST-FMR according to claim 1, characterized in that, The thickness of the ferromagnetic material layer is 10~100nm.

7. The spin filter based on ST-FMR according to claim 1, characterized in that, The electrode structure is disposed on the side of the ferromagnetic material layer and the heavy metal material layer, and the electrode structure forms an E-shaped structure or a Hall stripe structure with the stacked ferromagnetic material layer and the heavy metal material layer.

8. The spin filter based on ST-FMR according to claim 1, characterized in that, The signal transmission and processing module is a voltmeter or a phase-locked loop.

9. The spin filter based on ST-FMR according to claim 1, characterized in that, The radio frequency signal input module is an arbitrary waveform generator.

10. The spin filter based on ST-FMR according to claim 1, characterized in that, The DC current regulation module is a DC current source.

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