Nano low-pass filter based on Skyrmion spring oscillator

Abstract

The invention discloses a nano low-pass filter based on a skyrmion spring oscillator, which is characterized in that an antiferromagnetic coupled MnSi magnetic film structure is prepared, spin transfer torque is utilized to drive skyrmion to move, and a stable oscillation mode is formed through film boundary reflection; by changing the length Lx of the thin film and combining with an accurate mathematical formula, the oscillation frequency of the skyrmion is dynamically regulated and controlled, and high-precision adjustment of the cut-off frequency is achieved. Skyrmion oscillation shows an obvious high-frequency attenuation characteristic when an input signal is higher than a cut-off frequency, and an out-of-band signal is quickly cut off, so that out-of-band leakage is remarkably reduced, and the quality of a filtered signal is improved. The magneto-resistance effect is adopted to read oscillation response, a signal output structure is simplified, system power consumption is reduced, meanwhile, the anti-ferromagnetic coupling structure effectively suppresses spin Hall effect interference, and high stability of system operation is ensured.

Description

Technical Field

[0001] The invention relates to the technical field of nanotechnology and spin electronics, and in particular to a nano low-pass filter based on a skyrmion spring oscillator. Background Art

[0002] Nano low-pass filters are a type of signal processing device based on nanomaterials or nanostructures. They are widely used in electronics, optics, and microwave signal processing. They are mainly used to achieve selective filtering of signal frequencies, especially to suppress high-frequency out-of-band noise and ensure the purity and stability of the output signal. Their working principle usually relies on the control of structural design or material properties, and performs low-pass filtering on the input signal through a specific cutoff frequency.

[0003] In the prior art, in order to achieve low-pass filtering of nanometer-level signals, the following methods are usually adopted:

[0004] 1. Passive filters based on nanofilm structures: For example, selective filtering of specific frequency signals is achieved through nano-optical interference structures or discrete energy levels of quantum dots. However, the cutoff frequency of such filters is usually fixed and cannot be dynamically adjusted according to actual application requirements, which limits its applicability in variable signal scenarios.

[0005] 2. Through the electronic control characteristics of new materials such as graphene: For example, by using the adjustable band gap characteristics or high conductivity of graphene, selective response to specific frequency signals can be achieved. However, this solution is highly dependent on external electric fields or material preparation processes, the system performance is easily affected by external interference, and the attenuation characteristics of high-frequency signals are insufficient, which cannot meet the high requirements for filtering accuracy.

[0006] 3. Signal processing filters based on linear systems: Most existing filters are designed using linear systems. When faced with complex nonlinear dynamic signals, their response accuracy is limited, and it is difficult to efficiently process out-of-band noise. The filter output signal quality is poor.

[0007] In order to solve the above problems, some technical solutions in the industry introduce spin electronics mechanisms or spin dynamics systems to achieve filtering functions through the microscopic properties of magnetic materials. However, such solutions usually have the following disadvantages: Insufficient high-frequency attenuation performance: The cutoff frequency response of existing magnetic materials or structures is relatively slow, and it is impossible to "cut off" out-of-band signals, resulting in serious leakage of high-frequency noise. Lack of dynamic regulation capability: Once the structure of the magnetic material is determined, the cutoff frequency of the system cannot be flexibly adjusted, and it cannot adapt to the application requirements of multiple scenarios and multiple frequencies. Poor signal reading and stability: Due to the instability of the output signal of the magnetoresistance effect and external interference, the existing solutions are not stable enough when working for a long time, and the power consumption is high, which is not suitable for continuous application.

[0008] Therefore, how to dynamically adjust the cutoff frequency, improve the attenuation characteristics of high-frequency signals and reduce system power consumption has become a technical problem to be solved by the present invention. Summary of the invention

[0009] The technical problem solved by the present invention is to provide a nano low-pass filter based on a skyrmion spring oscillator in response to the defects existing in the above-mentioned prior art, so as to solve the problems of insufficient high-frequency attenuation, unadjustable cut-off frequency, poor stability and energy consumption performance proposed in the above-mentioned background technology.

[0010] In order to solve the above technical problems, the technical solution adopted by the present invention is as follows:

[0011] A nanometer low-pass filter based on a skyrmion spring oscillator, wherein the implementation method of the filter comprises the following steps:

[0012] Step 1, preparation of nanostructures:

[0013] First, a buffer layer of Cr is deposited on a glass substrate using magnetron sputtering technology;

[0014] Then, cobalt-iron electrodes and leads are deposited on the glass substrate using a mask or photolithography;

[0015] The magnetron sputtering technology is used to deposit MnSi magnetic material on the buffer layer Cr, and the construction size is L x ×Ly×Lznm 3 A nanodevice containing one skyrmion;

[0016] Where L x , Ly, and Lz are the length, width, and thickness of the nanodevice (in nanometers), respectively. Their numerical ranges are designed based on the dynamic oscillation stability of skyrmions, usually 50-500nm, 10-50nm, and 1-10nm. The nanodevice is designed to contain one skyrmion in order to optimize the stability of its oscillation mode and avoid the distortion of the oscillation frequency caused by the interaction between multiple skyrmions, thereby ensuring the accuracy and reliability of the filtering performance. The skyrmions are formed in an antiferromagnetically coupled MnSi film, which is prepared by magnetron sputtering technology, and the size parameters are strictly controlled to ensure the existence and stability of a single skyrmion. The surface and boundaries of the film are specially treated (such as silicon dioxide encapsulation) to enhance the controlled oscillation characteristics of skyrmions.

[0017] Depositing silicon dioxide on the entire device by methods including but not limited to chemical vapor deposition or sputtering deposition and encapsulating the device;

[0018] Step 2: Signal input and skyrmion motion drive:

[0019] Inputting the signal to be filtered into the nanostructure through the input end;

[0020] Applying current to the cobalt-iron electrode, the spin transfer torque is used to drive the skyrmions to move in the magnetic film.

[0021] The repulsive force at the film boundary is used to reflect skyrmions, forming a periodic oscillation pattern.

[0022] Step 3, dynamic frequency control:

[0023] By changing the length L of the magnetic film x To adjust the skyrmion oscillation mode and thus control the cutoff frequency of the filter, the film length L x The range is 50 to 500 nanometers. y Size is about L x Half of L z The range is 1 to 10 nanometers

[0024] Step 4, signal output and filtering effect:

[0025] A direct current is applied to the cobalt-iron electrode, and the response signal of the skyrmion oscillation is read using the magnetoresistance effect;

[0026] The output signal is a low-pass signal after filtering, and the low-pass filtering has a steep attenuation characteristic in the high-frequency signal range outside the cut-off frequency.

[0027] As a further solution of the present invention, the dynamic frequency control is achieved by the following formula:

[0028]

[0029] in:

[0030] f is the oscillation frequency of skyrmions;

[0031] γ is the gyro ratio constant;

[0032] H eff is the effective magnetic field inside the nanofilm;

[0033] L x is the actual length of the magnetic film;

[0034] L0 is the critical length required for stable oscillation of skyrmions;

[0035] The oscillation mode of skyrmions is controlled by the formula to realize dynamic adjustment of the filter cutoff frequency, thereby achieving a high-precision filtering effect on the input signal.

[0036] As a further solution of the present invention, the effective magnetic field H effThis is generated by applying an external magnetic field to the magnetic film, with the strength of the external magnetic field ranging from 0.1 Tesla to 2 Tesla to control the oscillation stability and response accuracy of the skyrmions.

[0037] As a further solution of the present invention, the oscillation mode of the skyrmion exhibits a nonlinear response when the input signal frequency is higher than the cutoff frequency, and the nonlinear response is used to enhance the attenuation characteristics of the high-frequency signal.

[0038] As a further embodiment of the present invention, the length L of the nanostructure x Dynamic regulation can be achieved by adjusting the size of the photolithography mask during the preparation process, and the size error of the mask is controlled within the range of ±1 nanometer to ensure the control accuracy of the cut-off frequency.

[0039] As a further embodiment of the present invention, the cobalt-iron electrode is used to generate a spin-polarized current, and the current density of the spin-polarized current is in the range of 10 6 ~10 8 A / cm 2 , the current density regulation is used to drive the oscillating motion of skyrmions.

[0040] As a further solution of the present invention, the magnetoresistance effect is achieved by applying a direct current to the cobalt-iron electrode of the nanostructure, wherein the direct current ranges from 1 to 5 mA, and the direct current is used to read a dynamic response signal of skyrmion oscillation.

[0041] Compared with the prior art, the present invention has the following beneficial effects:

[0042] 1. Through the dynamic response characteristics of the skyrmion spring oscillator, combined with the synergistic effect of spin transfer torque drive and boundary reflection, the skyrmion forms a highly stable oscillation mode within a specific frequency range. When the input signal frequency is higher than the cutoff frequency, the skyrmion oscillation shows obvious high-frequency attenuation characteristics; through the "clean cutoff" of the out-of-band signal by the skyrmion, fast and steep high-frequency attenuation is achieved, out-of-band signal leakage is reduced, and the purity and quality of the filter output signal are effectively improved.

[0043] 2. By changing the length L of the magnetic film x , realizing dynamic regulation of skyrmion oscillation frequency and cutoff frequency: using precise mathematical formulas for frequency control to ensure that the system response is accurate and controllable; unlike filters with fixed cutoff frequencies, this solution can quickly adapt to signal processing in different frequency ranges according to actual needs, greatly expanding the scope of application, and the combination of dynamic regulation and high-precision control, making the system more adaptable and flexible in complex and changeable signal processing.

[0044] 3. Through the antiferromagnetic coupled MnSi thin film structure, the signal interference caused by the spin Hall effect is effectively eliminated, ensuring that the oscillation motion of skyrmions is more stable; combined with the magnetoresistance effect signal reading technology, the output link of the filter signal is simplified, the circuit complexity and energy consumption are reduced, and the system characteristics of low power consumption and high efficiency are formed. The combination of this structural design and the reading mechanism not only improves the stability of the system, but also meets the application requirements of long-term continuous operation.

[0045] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0047] Figure 1 : Schematic diagram of the structure of the nano low-pass filter based on the skyrmion spring oscillator.

[0048] Figure 2 : Oscillation response curves of skyrmion spring oscillator at different input signal frequencies.

[0049] Figure 3 : Frequency response and cutoff characteristic curves of skyrmion spring oscillator. DETAILED DESCRIPTION

[0050] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0051] See also Figure 1 —3. In an embodiment of the present invention, a nanometer low-pass filter based on a skyrmion spring oscillator is provided. The implementation method of the filter comprises the following steps:

[0052] Step 1, preparation of nanostructures:

[0053] First, a buffer layer of Cr is deposited on a glass substrate using magnetron sputtering technology;

[0054] Then, cobalt-iron electrodes and leads are deposited on the glass substrate using a mask or photolithography;

[0055] The magnetron sputtering technology is used to deposit MnSi magnetic material on the buffer layer Cr, and the construction size is L x ×Ly×Lznm 3 A nanodevice containing one skyrmion;

[0056] Depositing silicon dioxide on the entire device by methods including but not limited to chemical vapor deposition or sputtering deposition and encapsulating the device;

[0057] Step 2: Signal input and skyrmion motion drive:

[0058] Inputting the signal to be filtered into the nanostructure through the input end;

[0059] Applying current to the cobalt-iron electrode, the spin transfer torque is used to drive the skyrmions to move in the magnetic film.

[0060] The repulsive force at the film boundary is used to reflect skyrmions, forming a periodic oscillation pattern.

[0061] Step 3, dynamic frequency control:

[0062] By changing the length L of the magnetic film x To adjust the skyrmion oscillation mode and thus control the cutoff frequency of the filter, the film length L x The range is 50 to 500 nanometers. y Size is about L x Half of L z The range is 1 to 10 nanometers

[0063] Step 4, signal output and filtering effect:

[0064] A direct current is applied to the cobalt-iron electrode, and the response signal of the skyrmion oscillation is read using the magnetoresistance effect;

[0065] The output signal is a low-pass signal after filtering, and the low-pass filtering has a steep attenuation characteristic in the high-frequency signal range outside the cut-off frequency.

[0066] As a further solution of the present invention, the dynamic frequency control is achieved by the following formula:

[0067]

[0068] in:

[0069] f is the oscillation frequency of skyrmions;

[0070] γ is the gyro ratio constant;

[0071] H eff is the effective magnetic field inside the nanofilm;

[0072] L x is the actual length of the magnetic film;

[0073] L0 is the critical length required for stable oscillation of skyrmions;

[0074] The oscillation mode of skyrmions is controlled by the formula to realize dynamic adjustment of the filter cutoff frequency, thereby achieving a high-precision filtering effect on the input signal.

[0075] As a further solution of the present invention, the effective magnetic field H eff This is generated by applying an external magnetic field to the magnetic film, with the strength of the external magnetic field ranging from 0.1 Tesla to 2 Tesla to control the oscillation stability and response accuracy of the skyrmions.

[0076] As a further solution of the present invention, the oscillation mode of the skyrmion exhibits a nonlinear response when the input signal frequency is higher than the cutoff frequency, and the nonlinear response is used to enhance the attenuation characteristics of the high-frequency signal.

[0077] As a further embodiment of the present invention, the length L of the nanostructure x Dynamic adjustment can be achieved by adjusting the size of the photolithography mask during the preparation process. The size error of the mask is controlled within the range of ±1 nanometer to ensure the control accuracy of the cut-off frequency. The cobalt-iron electrode is used to generate a spin-polarized current. The current density range of the spin-polarized current is 10 6 ~10 8 A / cm 2 The current density regulation is used to drive the oscillatory motion of skyrmions; the magnetoresistance effect is achieved by applying a direct current on the cobalt-iron electrode of the nanostructure, the direct current range is 1 to 5 mA, and the direct current is used to read the dynamic response signal of the skyrmion oscillation.

[0078] Embodiment 1:

[0079] The nanometer low-pass filter based on the skyrmion spring oscillator of the present invention is specifically applied to a microwave communication system for high-frequency signal processing, and is used to achieve accurate attenuation of high-frequency out-of-band noise and signal purification processing.

[0080] In microwave communication systems, the transmitted signals usually contain target signals and various interference signals, and the interference signals are mainly concentrated in the high-frequency range. When dealing with such interference, existing filters have problems such as insufficient high-frequency attenuation, out-of-band noise leakage, and low signal purity, which leads to a decline in the performance of the communication system and seriously affects the accuracy of data transmission. The present invention successfully solves this problem by combining skyrmion dynamics with dynamic control technology.

[0081] In practical applications, the filter of the present invention includes: nanostructure preparation: using magnetron sputtering technology to deposit a buffer layer (chromium), an antiferromagnetic coupled MnSi magnetic film and a protective layer (silicon dioxide) on a glass substrate in sequence. The thickness of the MnSi magnetic film is controlled to be 1 to 5 nanometers, and the film length L x The diameter of the nanostructured material is 64 to 128 nanometers, and the cobalt-iron electrode and copper electrode are formed by photolithography for input signal driving and output signal reading. The antiferromagnetic coupling design avoids the interference of the spin Hall effect and ensures the stability of the skyrmion oscillation.

[0082] Signal input and skyrmion motion control: The microwave signal to be processed enters the filter from the input port, and the frequency range of the input signal is 1 GHz to 20 GHz. A spin polarized current (current density of 10 6 ~10 8 A / cm 2 The skyrmions are driven to move in the film by the spin transfer torque. The movement of skyrmions is reflected by the repulsive force at the film boundary, forming a stable periodic oscillation mode.

[0083] Dynamic control and high-frequency signal attenuation: The filter adjusts the film length L x To achieve dynamic adjustment of the cutoff frequency, the following formula is used to control the oscillation frequency:

[0084]

[0085] The effective magnetic field H eff This can be achieved by applying an external magnetic field (strength of 0.1 to 2 Tesla). When the input signal frequency is higher than the filter cutoff frequency, the skyrmion oscillation exhibits significant high-frequency attenuation characteristics, and the out-of-band signal is quickly cut off, ensuring that the target signal is not affected by high-frequency interference.

[0086] Signal output and processing effect: The oscillation response signal of skyrmions is read by magnetoresistance effect, and the filtered target signal is output. The signal has higher purity and significantly improved signal-to-noise ratio. Compared with the traditional linear system filter, the present invention achieves steep attenuation characteristics in the high-frequency range, reduces the out-of-band signal leakage rate by more than 50%, and improves the signal-to-noise ratio of the target signal by more than 30%.

[0087] Embodiment 2:

[0088] The nano low-pass filter based on the skyrmion spring oscillator of the present invention is applied to a biomedical imaging system for efficient low-pass filtering of complex biological signals. In the field of biomedical imaging, such as magnetic resonance imaging (MRI) or electroencephalogram (EEG) signal processing, the signal often contains complex dynamic frequency components, and high-frequency noise and irregular interference signals easily affect the imaging quality and diagnostic accuracy. Existing filters are difficult to meet the processing requirements of biological signals in multiple scenarios due to their fixed frequency and insufficient high-frequency attenuation. The present invention provides a new solution for complex signal processing by combining skyrmion dynamics with nanoscale dynamic control technology.

[0089] In the specific implementation, the nano-film structure is first prepared by magnetron sputtering technology, including a buffer layer (chromium), an antiferromagnetically coupled MnSi magnetic film and a protective layer (silicon dioxide). The film length L x The frequency range of the biosignal is designed to be 64 to 128 nanometers, and the thickness is controlled at 1 to 5 nanometers to ensure the stability of skyrmion motion. Copper electrodes and cobalt-iron electrodes are formed by photolithography technology to input and read biosignals. The biosignals input into the system, such as EEG signals, usually have a frequency below 100 Hz, but are mixed with high-frequency noise ranging from hundreds to thousands of Hz, which seriously interferes with data analysis.

[0090] The present invention applies a spin-polarized current to the cobalt-iron electrode to drive the skyrmions to form a stable oscillating motion in the magnetic film. When the input signal frequency is higher than the set cutoff frequency, the high-frequency signal is quickly "cut off", making the output signal purer. In this application scenario, by adjusting the film length L x Or the strength of the external magnetic field (0.1 to 2 Tesla), the oscillation frequency of the skyrmions can be dynamically adjusted, and the filter can flexibly adapt to the processing needs of different patients or different biological signals.

[0091] The processed biological signal is read and output using the magnetoresistance effect, and the signal purity is improved by more than 30% compared with the traditional filter, and the out-of-band high-frequency noise suppression rate is improved by more than 50%. In the EEG signal processing, the present invention shows significant dynamic adaptability. It can still stably output high-quality signals in the case of strenuous exercise or high-frequency interference of the patient, providing technical guarantee for the improvement of diagnostic accuracy.

[0092] The application of the present invention effectively solves the problems of insufficient high-frequency noise suppression and unadjustable filter frequency in biomedical imaging signal processing, and realizes dynamic frequency control, precise attenuation of high-frequency signals and low-power signal processing through the innovative application of skyrmion dynamics.

[0093] Embodiment 3:

[0094] The dynamic frequency control filtering method based on the skyrmion spring oscillator of the present invention further verifies the specific implementation effect and advantages of the technical solution through experimental data and diagrams.

[0095] like Figure 1 As shown, Figure 1 This is a schematic diagram of the structure of a nano low-pass filter based on a skyrmion spring oscillator. The main components of the device include:

[0096] Cobalt-iron electrodes: The gray areas at both ends of the figure are cobalt-iron electrodes, which are responsible for input and output signals. By applying current, the cobalt-iron electrodes generate spin-polarized currents, driving skyrmions to move in the magnetic film.

[0097] Magnetic film (MnSi): The central region of the device is an antiferromagnetically coupled MnSi magnetic film with a thickness of 1nm, a width of 64nm, and a length of L x A single skyrmion is generated and stabilized inside the film. When an input signal current is applied, the skyrmion moves inside the film and reflects off the boundary to form a periodic oscillation pattern.

[0098] Input and output ends: II' (signal input): The input end transmits the signal to be filtered through the cobalt-iron electrode to stimulate the movement of skyrmions.

[0099] OO' (Signal Output): The output terminal reads the skyrmion oscillation response through the magnetoresistance effect and outputs a low-pass filtered signal.

[0100] Device packaging: The entire device is encapsulated by a silicon dioxide (SiO2) protective layer to ensure the stability and mechanical strength of the device in the environment.

[0101] Its working principle is: when the signal is applied from the input terminal II' to the cobalt iron electrode, the input current drives the skyrmions to move in the magnetic film through the spin transfer torque, and reflects at the film boundary to form a stable oscillation mode. x , the oscillation frequency of skyrmions can be dynamically adjusted to achieve precise control of the cutoff frequency. When the input signal frequency is higher than the cutoff frequency, the skyrmion oscillation exhibits a nonlinear response, and the high-frequency signal is rapidly attenuated; while the signal below the cutoff frequency can pass stably, completing the low-pass filtering function. Finally, the oscillation response is read through the signal output terminal OO' to obtain the filtered low-pass signal.

[0102] like Figure 2 As shown in the figure, the oscillation modes of the skyrmion spring oscillator at different input signal frequencies show obvious differences:

[0103] When the input signal frequency is low (such as 0.1GHz), skyrmions exhibit a large oscillation amplitude in the nanofilm, with obvious and stable periodicity.

[0104] As the frequency of the input signal gradually increases (such as 0.4GHz, 1.08GHz, 1.5625GHz), the oscillation amplitude of the skyrmions gradually decreases, and the oscillation frequency shows a nonlinear response relationship with the input signal frequency.

[0105] This shows that the skyrmion dynamic response is frequency selective, and high-frequency signals cannot effectively drive skyrmions to form large-amplitude oscillations. This characteristic provides a physical basis for achieving rapid attenuation of high-frequency signals.

[0106] like Figure 3 As shown, when the film length L x = 128nm, the frequency response curve of the skyrmion spring oscillator shows a significant cutoff characteristic: when the input frequency is close to 1.2GHz, the oscillation amplitude shows a significant "steep drop", and the high-frequency signal is effectively suppressed. This phenomenon proves the "clean cutoff" advantage of the present invention in high-frequency signal processing, which can achieve efficient attenuation of out-of-band noise and ensure the purity of the output signal.

[0107] In summary, this embodiment experimentally verifies the frequency selection characteristics and high-frequency attenuation capability of the skyrmion dynamic response, and further illustrates the remarkable technical effects of the present invention in dynamically controlling the cutoff frequency, rapidly attenuating high-frequency signals, and improving the quality of filtered signals.

[0108] In the present invention, unless otherwise clearly stipulated and limited, the terms such as "installation", "setting", "connection", "fixation" and "screw-on" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be the internal connection of two elements or the interaction relationship between two elements. Unless otherwise clearly defined, ordinary technicians in this field can understand the specific meanings of the above terms in the present invention according to the specific circumstances.

[0109] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be considered exemplary and non-restrictive in all respects, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims be included in the present invention.

Claims

1. A nanometer low-pass filter based on a skyrmion spring oscillator, characterized in that: The implementation method of the filter includes the following steps: Step 1, preparation of nanostructures: Firstly, a buffer layer of Cr is deposited on a glass substrate using magnetron sputtering technology; Then, cobalt-iron electrodes and leads are deposited on the glass substrate using a mask or photolithography; The magnetron sputtering technology is used to deposit MnSi magnetic material on the buffer layer Cr, and the construction size is L x ×Ly×Lznm 3 A nanodevice containing one skyrmion; Depositing silicon dioxide on the entire device by methods including but not limited to chemical vapor deposition or sputtering deposition and encapsulating the device; Step 2: Signal input and skyrmion motion drive: Inputting the signal to be filtered into the nanostructure through the input end; Applying current to the cobalt-iron electrode, the spin transfer torque is used to drive the skyrmions to move in the magnetic film. The repulsive force at the film boundary is used to reflect skyrmions, forming a periodic oscillation pattern. Step 3, dynamic frequency control: By changing the length L of the magnetic film x To adjust the skyrmion oscillation mode and thus control the cutoff frequency of the filter, the film length L x The range is 50 to 500 nanometers. y Size is about L x Half of L z The range is 1 to 10 nanometers Step 4, signal output and filtering effect: A direct current is applied to the cobalt-iron electrode, and the response signal of the skyrmion oscillation is read using the magnetoresistance effect; The output signal is a low-pass signal after filtering, and the low-pass filtering has a steep attenuation characteristic in the high-frequency signal range outside the cut-off frequency.

2. The nanometer low-pass filter based on skyrmion spring oscillator according to claim 1, characterized in that: The dynamic frequency control is achieved by the following formula: in: f is the oscillation frequency of skyrmions; γ is the gyro ratio constant; H eff is the effective magnetic field inside the nanofilm; L x is the actual length of the magnetic film; L0 is the critical length required for stable oscillation of skyrmions; The cut-off frequency of the filter is adjusted by controlling the oscillation mode of the skyrmion through the formula.

3. The nanometer low-pass filter based on skyrmion spring oscillator according to claim 2, characterized in that: The effective magnetic field H eff The magnetic film is generated by applying an external magnetic field to the magnetic film, wherein the strength of the external magnetic field is in the range of 0.1 Tesla to 2 Tesla.

4. The nanometer low-pass filter based on skyrmion spring oscillator according to claim 2, characterized in that: The oscillation mode of the skyrmion exhibits a nonlinear response when the input signal frequency is higher than the cutoff frequency.

5. The nanometer low-pass filter based on skyrmion spring oscillator according to claim 2, characterized in that: The length L of the nanostructure x Dynamic regulation can be achieved by adjusting the size of the photolithography mask during the preparation process, and the size error of the mask is controlled within the range of ±1 nanometer.

6. The nanometer low-pass filter based on skyrmion spring oscillator according to claim 1, characterized in that: The cobalt-iron electrode is used to generate a spin-polarized current, and the current density of the spin-polarized current is in the range of 10 6 ~10 8 A / cm 2 , the current density regulation is used to drive the oscillating motion of skyrmions.

7. The nanometer low-pass filter based on skyrmion spring oscillator according to claim 1, characterized in that: The magnetoresistance effect is achieved by applying a direct current on the cobalt-iron electrode of the nanostructure, wherein the direct current ranges from 1 to 5 mA, and the direct current is used to read a dynamic response signal of skyrmion oscillation.

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