Vibration phase bit coding test method and device based on graphene parameter resonator

Abstract

The invention discloses a vibration phase bit coding test method and device based on a graphene parameter resonator, and relates to the technical field of resonators. The method comprises the following steps: applying an initial bias voltage and a parameter excitation signal, and setting the driving frequency of the parameter excitation signal to be twice of the resonant frequency corresponding to the initial bias voltage; continuously increasing the parameter excitation signal until the resonator enters a parameter vibration state; applying a direct driving signal, and setting the driving frequency of the direct driving signal as the resonant frequency corresponding to the initial bias voltage; selecting bias voltage values on two sides of the initial bias voltage, and scanning from low to high and from high to low to obtain vibration phase change; and obtaining the vibration phase bit code of the to-be-measured graphene parameter resonator according to the vibration phase change. Information is stored through mechanical vibration of the graphene parameter resonator instead of utilizing charge or electron spinning, electromagnetic interference and phase noise are effectively avoided, and the graphene parameter resonator is more stable at high temperature and suitable for a high electromagnetic noise environment.

Description

Technical Field

[0001] This invention relates to a method and apparatus for testing the vibration phase bit encoding of a graphene parametric resonator, belonging to the field of resonator technology. Background Technology

[0002] Electronic bits are the basic units of information in digital systems; all information is composed of binary values ​​0 and 1. As the core of digital electronics, traditional electronic bits use voltage pulses to represent binary states, forming the basis of digital circuits and storage devices for data storage, processing, and communication. Furthermore, their evolution has driven advancements in computing, storage, and emerging fields such as quantum and probabilistic computing.

[0003] Thanks to the development and standardization of modern manufacturing technology, electronic bit systems have become relatively mature, characterized by high speed and high density, supporting modern processors to achieve extremely fast computation and large-scale data storage. However, electronic bits are very sensitive to temperature, radiation, and electromagnetic interference, and their susceptibility to harsh environments limits their use under extreme conditions.

[0004] In contrast, mechanical bits offer greater stability because their functionality is based on mechanical motion, which can persist even in extreme environments such as high temperatures, low temperatures, or nuclear radiation. Furthermore, mechanical bit systems can be constructed and manufactured from a variety of materials, and the properties of these materials can further enhance their adaptability to extreme environments. For example, mechanical systems made with insulating materials are resistant to electric shock and less susceptible to electrical interference and shocks, making them suitable for certain specific applications.

[0005] Currently, most mechanical bits are implemented based on mechanical resonators. The simplest and most common method is to treat the nonlinear large-amplitude oscillation and small-amplitude oscillation of the resonator as the two states of the mechanical bit, and control the resonator to enter the nonlinear large-amplitude oscillation state or the small-amplitude oscillation state by scanning the drive frequency. However, for resonators of different sizes, the amplitude values ​​of the nonlinear large-amplitude oscillation and the small-amplitude oscillation vary greatly by orders of magnitude, so the two states of the mechanical bit must be redefined for each resonator.

[0006] As an improvement, a novel approach utilizes a parametric resonator to define the mechanical bit. In a mechanical system, the dynamic behavior of a parametric resonator is caused by the interaction between parametric excitation and direct drive. The parametric excitation drives the resonator to vibrate by modulating its resonant frequency; when the parametric excitation is sufficiently large, the resonator enters a parametric vibration state. Without direct drive, this parametric resonator exhibits two degenerate vibration modes with the same amplitude but different phases. Radius. This degeneracy can be eliminated by adding a direct drive to the parametric excitation. Far from the resonant frequency, the resonator primarily responds to the direct drive, meaning that the vibrations far below and far above the resonant frequency are out of phase. Radians. Directly driven angular frequency by scanning from a distance. and the angular frequency of the excitation pump ; By directing it through the resonant frequency, the phase of the parametric resonator can be kept consistent with the phase deviating from the resonant frequency. In other words, by controlling the scanning direction of the direct drive signal frequency and the parametric excitation signal frequency, the phase of the non-degenerate state can be selected independently. The advantage of this method is that regardless of the resonator's size, the phase difference between the two degenerate states of its parametric vibration is always... radian.

[0007] However, the above methods also have drawbacks. In practical applications, changing the driving frequency can easily cause the phase of the driving waveform to become discontinuous, which in turn generates phase noise. For nanoscale resonators and high-frequency resonators, the presence of phase noise can easily cause the resonator to randomly transition between two phases, that is, it is impossible to stably control the phase. The large-scale integration and fast operation capability of mechanical bits require the resonator size to be nanoscale and the operating frequency to be high frequency. Furthermore, the method of controlling the scanning direction of the direct driving signal frequency and the parameter excitation signal frequency is not simple to implement. Summary of the Invention

[0008] The purpose of this invention is to overcome the shortcomings of the prior art and provide a vibration phase bit encoding test method and device based on graphene parametric resonators. By storing information through the mechanical vibration of graphene parametric resonators instead of using charge or electron spin, electromagnetic interference and phase noise can be effectively avoided. Furthermore, it is more stable at high temperatures and is suitable for high electromagnetic noise environments.

[0009] To achieve the above objectives, the present invention is implemented using the following technical solution: On one hand, the present invention provides a method for testing the vibration phase bit encoding based on a graphene parametric resonator, comprising: An initial bias voltage is applied to the gate DC signal terminal of the resonator of the graphene parameter under test; A parameter excitation signal is applied to the gate RF signal terminal of the graphene parametric resonator under test, and the driving frequency of the parameter excitation signal is set to twice the resonant frequency corresponding to the initial bias voltage. The intensity of the parameter excitation signal is continuously increased until the graphene parameter resonator under test enters the parameter vibration state; To maintain the parameter oscillation state of the graphene resonator under test, a direct drive signal is applied to the gate RF signal terminal of the graphene resonator under test, and the drive frequency of the direct drive signal is set to the resonant frequency corresponding to the initial bias voltage. The bias voltage values ​​on both sides of the initial bias voltage are selected as the high bias voltage value and the low bias voltage value. The vibration phase change of the resonator of the graphene parameter under test is obtained by scanning from the low bias voltage value to the high bias voltage value and from the high bias voltage value to the low bias voltage value. The vibration phase bit code of the resonator with the graphene parameters under test is obtained based on the vibration phase change of the resonator with the graphene parameters under test.

[0010] Furthermore, the method for determining the resonant frequency corresponding to the initial bias voltage includes: Based on the vibration signal intensity curve function of the driving frequency and bias voltage of the resonator of the graphene parameter under test, the horizontal axis is taken as the initial bias voltage, and the driving frequency when the vibration signal intensity is the strongest is the resonant frequency corresponding to the initial bias voltage. Alternatively, an initial bias voltage is applied to the DC signal terminal of the gate of the graphene resonator under test, and a direct drive signal is applied to the RF signal terminal of the gate, while the parameter excitation signal is in the off state. The driving frequency of the direct drive signal is continuously changed, and the vibration signal intensity corresponding to the driving frequency of each direct drive signal is recorded. The driving frequency of the direct driving signal when the vibration signal intensity is strongest is the resonant frequency corresponding to the initial bias voltage.

[0011] Furthermore, the method for determining whether the graphene resonator under test has entered a parametric vibration state is as follows: Determine the vibration signal intensity threshold; As the excitation signal strength is gradually increased from zero, the vibration signal strength of the graphene resonator under test is observed until the vibration signal strength exceeds the vibration signal strength threshold, which indicates that the graphene resonator under test has entered the parametric vibration state. The method for determining the vibration signal intensity threshold includes: Based on the vibration signal intensity curve function of the driving frequency and bias voltage of the resonator of the graphene parameter under test, the horizontal axis is taken as the initial bias voltage, and the vertical axis is taken as the vibration signal intensity at the resonant frequency corresponding to the initial bias voltage, which is the vibration signal intensity threshold. Alternatively, an initial bias voltage is applied to the DC signal terminal of the gate of the resonator of the graphene parameter under test, and a direct drive signal is applied to the RF signal terminal of the gate. The driving frequency of the direct drive signal is set to the resonant frequency corresponding to the initial bias voltage. The vibration signal intensity at this time is the vibration signal intensity threshold.

[0012] Furthermore, the method for obtaining the vibration signal intensity curve function of the driving frequency and bias voltage of the graphene resonator under test includes: S1. Apply a direct drive signal to the gate RF signal terminal of the graphene resonator under test, while the parameter excitation signal is in the off state, and apply a bias voltage to the gate DC signal terminal. S2. Select a bias voltage, keep the bias voltage constant, change the driving frequency of the direct driving signal within the preset driving frequency range, and measure the vibration signal intensity corresponding to each driving frequency. S3. Select the next bias voltage, keep the bias voltage unchanged, change the driving frequency of the direct driving signal within the preset driving frequency range, and measure the vibration signal intensity corresponding to each driving frequency. S4. Repeat S2~S4 until all bias voltages within the preset bias voltage range are selected. Combine the vibration signal intensity of the driving frequency and the bias voltage of the graphene parameter resonator under test with the driving frequency of the different direct driving signals corresponding to each bias voltage to obtain the vibration signal intensity curve function of the driving frequency and the bias voltage of the resonator under test.

[0013] Furthermore, the waveform amplitude of the direct drive signal satisfies the requirement that the graphene resonator under test is always in the linear vibration domain, that is, the waveform amplitude of the direct drive signal is linearly related to the intensity of the vibration signal.

[0014] Furthermore, the waveform expression of the direct drive signal is as follows: ; The waveform expression of the parameter excitation signal is as follows: ; in, Indicates the direct drive angular frequency. This represents the phase difference between the direct drive signal and the parameter excitation signal. Indicates the excitation angular frequency. Indicates the amplitude of the direct drive signal waveform. This represents the amplitude of the excitation signal waveform. Indicates time; The phase difference between the direct drive signal and the parameter excitation signal Set to -45°.

[0015] Furthermore, the graphene resonator under test was tested under vacuum conditions.

[0016] On the other hand, the present invention also provides a vibration phase bit encoding test device based on a graphene parametric resonator, used to implement the vibration phase bit encoding test method based on a graphene parametric resonator as described in any of the above claims. It includes a helium-neon laser, which is used to emit a laser beam to a half-wave plate. The laser beam passing through the half-wave plate is reflected by a reflection component and transmitted to a polarization beam splitter. Then, it is incident on an objective lens through a quarter-wave plate. A vacuum cavity is provided on the other side of the objective lens. The vacuum cavity is used to place the graphene parametric resonator to be tested. The objective lens is used to focus the laser beam and incident it on the surface of the graphene parametric resonator to be tested through the vacuum cavity. The polarization beam splitter is connected to a photodetector, and the output of the photodetector is sequentially connected to a lock-in amplifier and an arbitrary waveform generator. One output terminal of the arbitrary waveform generator is connected to the gate radio frequency signal terminal of the graphene parameter resonator under test, and the other output terminal is connected to the reference signal input terminal of the lock-in amplifier. The arbitrary waveform generator is used to transmit the reference signal to the lock-in amplifier and to apply the parameter excitation signal and the direct drive signal to the gate of the graphene parameter resonator under test. It also includes a DC voltage source, which is connected to the gate DC signal terminal of the graphene parameter resonator under test, and the DC voltage source is used to apply a bias voltage to the gate of the graphene parameter resonator under test.

[0017] Furthermore, the reflective assembly includes two mirrors placed symmetrically, which are used to transmit the laser beam to the polarization beam splitter in a direction opposite to the initial emission direction after two 90° emission.

[0018] Furthermore, the waveform expression of the reference signal is as follows: ; in, Indicates the direct drive angular frequency. Indicates the amplitude of the reference signal waveform. Indicates time, This represents the phase difference between the direct drive signal and the parameter excitation signal.

[0019] Compared with the prior art, the beneficial effects achieved by the present invention are as follows: This invention stores information through the mechanical vibration of a graphene parametric resonator, rather than using charge or electron spin, which can effectively avoid electromagnetic interference and is more stable at high temperatures, making it suitable for high electromagnetic noise environments. The energy decay of the graphene parametric resonator is very slow at low temperatures, which can reduce errors caused by signal attenuation, making it more suitable for quantum information storage and computation in low-temperature environments. Attached Figure Description

[0020] Figure 1This is a schematic diagram of the structure of a vibration phase bit encoding test device based on a graphene parametric resonator in one embodiment of the present invention; Figure 2 This is a schematic cross-sectional view of the resonator with the graphene parameters to be tested in Embodiment 2 of the present invention; Figure 3 This is a schematic diagram of the vibration signal intensity curve function of the driving frequency and gate voltage of the resonator of the graphene parameter under test in Embodiment 2 of the present invention; Figure 4 This is a schematic diagram of the signal intensity and vibration phase changes of the resonator under test obtained by scanning the DC signal terminal of the gate of the resonator under test by changing the bias voltage value applied to it in Embodiment 2 of the present invention. Detailed Implementation

[0021] The present invention will be further described below with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and should not be used to limit the scope of protection of the present invention.

[0022] Example 1

[0023] like Figure 1 As shown, this embodiment of the invention provides a vibration phase bit encoding test device based on a graphene parametric resonator, including a helium-neon laser. The helium-neon laser is used to emit a laser beam to a half-wave plate, and the half-wave plate is used to adjust the energy ratio of the horizontal polarization component and the vertical polarization component in the beam.

[0024] The laser beam passing through the half-wave plate is transmitted to the polarization beam splitter via a reflecting component. In this embodiment, the reflecting component consists of two symmetrically arranged mirrors, allowing the laser beam to be emitted twice at 90° angles and then transmitted to the polarization beam splitter in a direction opposite to the initial emission direction. The polarization beam splitter reflects the vertically polarized component out of the optical path, allowing the horizontally polarized component to pass through. The horizontal p-wave component is converted into circularly polarized light by a quarter-wave plate and incident on the objective lens.

[0025] A vacuum chamber is provided on the other side of the objective lens. The graphene parameter resonator to be tested is placed inside the vacuum chamber. Circularly polarized light is focused through the objective lens and then incident on the surface of the graphene parameter resonator to be tested through the vacuum chamber.

[0026] The polarization beam splitter is connected to a photodetector, which converts the optical signal into an electrical signal and outputs it to a lock-in amplifier. The output of the lock-in amplifier is connected to the input port of an arbitrary waveform generator. The arbitrary waveform generator has two output ports, one of which is connected to the reference signal input of the lock-in amplifier and is used to transmit the reference signal to the lock-in amplifier.

[0027] The waveform expression of the reference signal is as follows ,in, Indicates the direct drive angular frequency. Indicates the amplitude of the reference signal waveform. Indicates time, This indicates the phase difference between the direct drive signal and the parameter excitation signal. The other output port is connected to the gate RF signal terminal of the graphene resonator under test, used to apply the parameter excitation signal or the direct drive signal to the gate of the graphene resonator under test.

[0028] The reflected laser beam from the surface of the graphene resonator under test passes through the objective lens and the quarter-wave plate in sequence. Its polarization direction becomes perpendicular to the objective lens. Therefore, the reflected laser beam cannot pass through the polarization beam splitter and is reflected into the photodetector.

[0029] The DC signal terminal of the gate of the graphene resonator under test is also connected to a DC voltage source, which is used to apply a bias voltage to the gate of the graphene resonator under test.

[0030] Example 2

[0031] Based on Example 1, this example also provides a vibration phase bit encoding test method based on a graphene parametric resonator, including the following steps: In this embodiment, the graphene parameter resonator under test is a bilaterally fixed strip-shaped few-layer graphene nanomechanical resonator, the structure of which is as follows: Figure 2 As shown in the figure, green represents the graphene film, yellow represents the electrodes, the middle electrode that is not in contact with the graphene is the gate electrode, and the electrodes on both sides that are in contact with the graphene are the source and drain electrodes, respectively. Gray represents silicon dioxide, and the graphene film is suspended above a 3μm trench.

[0032] Before the formal test begins, it is necessary to obtain the vibration signal intensity curve function of the driving frequency and bias voltage of the graphene parametric resonator under test, as well as the threshold used to determine whether the graphene parametric resonator under test enters the parametric vibration state.

[0033] The function for obtaining the vibration signal intensity curves of the driving frequency and bias voltage of the resonator of the graphene under test includes: S1. A direct drive signal is applied to the gate RF signal terminal of the graphene resonator under test, while the parameter excitation signal is in the off state, and a bias voltage is applied to the gate DC signal terminal. In this embodiment, the waveform amplitude of the direct drive signal is 9mVpp. It should be noted that whenever a direct drive signal is applied, the resonator must be in the linear vibration region, that is, the waveform amplitude of the direct drive signal is linearly related to the intensity of the vibration signal.

[0034] S2. Select a bias voltage, keep the bias voltage constant, change the driving frequency of the direct driving signal within the preset driving frequency range, and measure the vibration signal intensity corresponding to each driving frequency. S3. Select the next bias voltage, keep the bias voltage unchanged, change the driving frequency of the direct driving signal within the preset driving frequency range, and measure the vibration signal intensity corresponding to each driving frequency. S4. Repeat S2~S4 until all bias voltages within the preset bias voltage range have been selected. The vibration signal intensity curve function of the driving frequency and bias voltage of the resonator under test is obtained by combining the vibration signal intensity at the driving frequency of different direct driving signals corresponding to each bias voltage. Figure 3 As shown, the resonant frequency and the driving signal intensity curve of the bias voltage form a "V" shape. The point on the V-shape is the driving frequency of the direct driving signal corresponding to the maximum vibration signal intensity under a bias voltage, which is the resonant frequency corresponding to this bias voltage.

[0035] Methods for determining the threshold used to judge whether a graphene resonator under test enters a parametric vibration state include: An initial bias voltage is applied to the DC signal terminal of the gate of the graphene resonator under test, and a direct drive signal is applied to the RF signal terminal of the gate. The driving frequency of the direct drive signal is set to the resonant frequency corresponding to the initial bias voltage, and the vibration signal intensity at this time is used as the vibration signal intensity threshold.

[0036] Alternatively, the vibration signal intensity curve function of the driving frequency and bias voltage of the resonator of the graphene parameter under test can be directly read. The horizontal axis is the initial bias voltage, and the vertical axis is the vibration signal intensity at the resonant frequency corresponding to the initial bias voltage, which is the vibration signal intensity threshold.

[0037] The vibration phase bit encoding of the resonator with the parameters of the graphene under test will now be tested. The test method is as follows: The graphene resonator under test is placed in a vacuum chamber with the graphene film of the resonator facing the objective lens and the source and drain electrodes grounded.

[0038] The reason for choosing graphene parametric resonators is that graphene has obvious conservatism and dissipative nonlinearity, which is conducive to observing the degeneracy removal phenomenon of the resonator's parametric vibration. In addition, the excellent frequency tunability of graphene parametric resonators provides a good foundation for low-energy parameter excitation to excite parametric vibration, and the high operating frequency also helps to expand the width of the mechanical phase bit's operating region.

[0039] An initial bias voltage is applied to the gate DC signal terminal of the graphene resonator under test using a DC voltage source. The bias voltage is selected only if the graphene resonator under test is in a linear vibration mode, i.e., in a state of... Figure 3 Furthermore, it is better to select the bias voltage corresponding to the point with a larger signal strength on the "V-shape". In this embodiment, the initial bias voltage is 2.4V.

[0040] A parameter excitation signal (with the direct drive signal off) is applied to the gate RF signal terminal of the graphene resonator under test using an arbitrary waveform generator. The waveform expression of the parameter excitation signal is as follows: ,in, Indicates the excitation angular frequency. This represents the amplitude of the excitation signal waveform. This indicates the time. The driving frequency of the excitation signal is set to twice the resonant frequency corresponding to the initial bias voltage. The resonant frequency corresponding to the initial bias voltage is determined using the following method: Method 1: Combining Figure 3 The function of the vibration signal intensity curve of the driving frequency and bias voltage of the resonator of the graphene under test is used. The horizontal axis is the initial bias voltage value. The vertical axis frequency is the frequency corresponding to the strongest vibration signal intensity (the strongest vibration signal intensity is the highest brightness, which can be seen to be on the "V" shape) at the initial bias voltage value. This frequency is the resonant frequency corresponding to the initial bias voltage, and the strongest vibration signal intensity is also the vibration signal intensity threshold.

[0041] Method 2: Using the initial bias voltage as the gate voltage, enable the direct drive waveform signal output and disable the parameter excitation signal output. Continuously change the drive frequency of the direct drive signal and record the vibration signal intensity through a lock-in amplifier. The drive frequency corresponding to the strongest vibration signal intensity is the resonant frequency corresponding to the initial bias voltage, and the strongest vibration signal intensity is also the vibration signal intensity threshold.

[0042] The applied excitation signal is continuously increased until the graphene resonator under test enters a parametric vibration state. In this embodiment, the method for determining whether the graphene resonator under test has entered a parametric vibration state is as follows: Turn off the direct drive signal, turn on the parameter excitation signal, and set the drive frequency of the parameter excitation signal to twice the resonant frequency corresponding to the initial bias voltage. Gradually increase the intensity of the parameter excitation signal from zero, and observe the intensity of the resonator's vibration signal.

[0043] Based on the determined vibration signal intensity threshold, when the resonator has not entered the parametric vibration state, the vibration signal intensity will always be significantly lower than the recorded threshold. When the vibration signal intensity suddenly exceeds the recorded vibration signal intensity threshold, it indicates that the graphene parametric resonator under test has entered the parametric vibration state.

[0044] A direct drive signal (with a simultaneous parameter excitation signal) is applied to the gate of the graphene resonator under test. The value of the direct drive signal is sufficient to ensure that the graphene resonator under test is in the linear vibration region. In this embodiment, the waveform expression of the direct drive signal is as follows: ,in, Indicates the direct drive angular frequency. Indicates the amplitude of the direct drive signal waveform. Indicates time, This represents the phase difference between the direct drive signal and the parametric excitation signal. The driving frequency of the direct drive signal is set to the resonant frequency corresponding to the initial bias voltage to disrupt the degeneracy of the parametric vibrations of the graphene parametric resonator under test.

[0045] It should be noted that, in this embodiment, the phase difference between the direct drive signal and the parameter pump excitation signal... It is set to -45°, but not limited to this; other phase differences should also be acceptable, but -45° satisfies any graphene parameter resonator.

[0046] The bias voltage applied to the DC signal terminal of the gate of the graphene resonator under test was changed, linearly increasing from 2V to 3V and then linearly increasing from 3V back to 2V. The phase change and signal intensity change of the graphene resonator under test were recorded by a lock-in amplifier. Figure 4 As shown, when the gate voltage increases to 2.4V, the phase of the resonator is... When the gate voltage drops to 2.4V, the resonator's phase is 0, and it will later jump back to its previous state. .

[0047] Therefore, the mechanical phase bits can be flipped and stored through the following operations: Set the bias voltage of 2.4V as the initial bias voltage. If you want to flip the mechanical phase bits to... If you want to flip the mechanical phase bit to 0, then perform a voltage scan operation of 2.4V-2V-2.4V; if you want to flip the mechanical phase bit to 0, then perform a voltage scan operation of 2.4V-3V-2.4V; if you just want to save the existing mechanical phase bit state, then keep the 2.4V bias voltage unchanged.

[0048] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for testing the vibration phase bit encoding based on a graphene parametric resonator, characterized in that, include: An initial bias voltage is applied to the gate DC signal terminal of the resonator of the graphene parameter under test; A parameter excitation signal is applied to the gate RF signal terminal of the graphene parametric resonator under test, and the driving frequency of the parameter excitation signal is set to twice the resonant frequency corresponding to the initial bias voltage. The intensity of the parameter excitation signal is continuously increased until the graphene parameter resonator under test enters the parameter vibration state; To maintain the parameter oscillation state of the graphene resonator under test, a direct drive signal is applied to the gate RF signal terminal of the graphene resonator under test, and the drive frequency of the direct drive signal is set to the resonant frequency corresponding to the initial bias voltage. The bias voltage values ​​on both sides of the initial bias voltage are selected as the high bias voltage value and the low bias voltage value, respectively. The vibration phase change of the graphene resonator under test is obtained by scanning from the low bias voltage value to the high bias voltage value and from the high bias voltage value to the low bias voltage value. The vibration phase bit code of the resonator with the graphene parameters under test is obtained based on the vibration phase change of the resonator with the graphene parameters under test.

2. The vibration phase bit encoding test method based on graphene parametric resonator according to claim 1, characterized in that, The method for determining the resonant frequency corresponding to the initial bias voltage includes: Based on the vibration signal intensity curve function of the driving frequency and bias voltage of the resonator of the graphene parameter under test, the horizontal axis is taken as the initial bias voltage, and the driving frequency when the vibration signal intensity is the maximum is the resonant frequency corresponding to the initial bias voltage. Alternatively, an initial bias voltage is applied to the DC signal terminal of the gate of the graphene resonator under test, and a direct drive signal is applied to the RF signal terminal of the gate, while the parameter excitation signal is in the off state. The driving frequency of the direct drive signal is continuously changed, and the vibration signal intensity corresponding to the driving frequency of each direct drive signal is recorded. The driving frequency of the direct driving signal when the vibration signal intensity is at its maximum is the resonant frequency corresponding to the initial bias voltage.

3. The vibration phase bit encoding test method based on graphene parametric resonators according to claim 1, characterized in that, The method for determining whether the graphene resonator under test has entered the parametric vibration state is as follows: Determine the vibration signal intensity threshold; As the excitation signal strength is gradually increased from zero, the vibration signal strength of the graphene resonator under test is observed until the vibration signal strength exceeds the vibration signal strength threshold, which indicates that the graphene resonator under test has entered the parametric vibration state. The method for determining the vibration signal intensity threshold includes: Based on the vibration signal intensity curve function of the driving frequency and bias voltage of the resonator of the graphene parameter under test, the horizontal axis is taken as the initial bias voltage, and the vertical axis is taken as the vibration signal intensity at the resonant frequency corresponding to the initial bias voltage, which is the vibration signal intensity threshold. Alternatively, an initial bias voltage is applied to the DC signal terminal of the gate of the resonator of the graphene parameter under test, and a direct drive signal is applied to the RF signal terminal of the gate. The driving frequency of the direct drive signal is set to the resonant frequency corresponding to the initial bias voltage. The vibration signal intensity at this time is the vibration signal intensity threshold.

4. The vibration phase bit encoding test method based on graphene parametric resonators according to claim 2 or 3, characterized in that, The method for obtaining the vibration signal intensity curve function of the driving frequency and bias voltage of the resonator of the graphene parameter under test includes: S1. Apply a direct drive signal to the gate RF signal terminal of the graphene resonator under test, while the parameter excitation signal is in the off state, and apply a bias voltage to the gate DC signal terminal. S2. Select a bias voltage, keep the bias voltage constant, change the driving frequency of the direct driving signal within the preset driving frequency range, and measure the vibration signal intensity corresponding to each driving frequency. S3. Select the next bias voltage, keep the bias voltage unchanged, change the driving frequency of the direct driving signal within the preset driving frequency range, and measure the vibration signal intensity corresponding to each driving frequency. S4. Repeat S2~S4 until all bias voltages within the preset bias voltage range are selected. Combine the vibration signal intensity of the driving frequency and the bias voltage of the graphene parameter resonator under test with the driving frequency of the different direct driving signals corresponding to each bias voltage to obtain the vibration signal intensity curve function of the driving frequency and the bias voltage of the resonator under test.

5. The vibration phase bit encoding test method based on graphene parametric resonator according to claim 1, characterized in that, The waveform amplitude of the direct drive signal is such that the resonator of the graphene parameter under test is always in the linear vibration domain.

6. The vibration phase bit encoding test method based on graphene parametric resonator according to claim 1, characterized in that, The waveform expression of the direct drive signal is as follows: ; The waveform expression of the parameter excitation signal is as follows: ; in, Indicates the direct drive angular frequency. This represents the phase difference between the direct drive signal and the parameter excitation signal. Indicates the excitation angular frequency. Indicates the amplitude of the direct drive signal waveform. This represents the amplitude of the excitation signal waveform. Indicates time; The phase difference between the direct drive signal and the parameter excitation signal Set to -45°.

7. The vibration phase bit encoding test method based on graphene parametric resonator according to claim 1, characterized in that, The graphene resonator under test was tested under vacuum conditions.

8. A vibration phase bit encoding testing device based on a graphene parametric resonator, characterized in that, The method for implementing the vibration phase bit encoding test method based on graphene parametric resonators as described in any one of claims 1 to 7 includes a helium-neon laser, which emits a laser beam toward a half-wave plate. The laser beam is reflected by a reflection component and transmitted to a polarization beam splitter, and then incident on an objective lens through a quarter-wave plate. A vacuum cavity is provided on the other side of the objective lens, which is used to place the graphene parametric resonator under test. The objective lens is used to focus the laser beam and incident it onto the surface of the graphene parametric resonator under test through the vacuum cavity. The polarization beam splitter is connected to a photodetector, and the output of the photodetector is sequentially connected to a lock-in amplifier and an arbitrary waveform generator. One output terminal of the arbitrary waveform generator is connected to the gate radio frequency signal terminal of the graphene parameter resonator under test, and the other output terminal is connected to the reference signal input terminal of the lock-in amplifier. The arbitrary waveform generator is used to transmit the reference signal to the lock-in amplifier and to apply the parameter excitation signal and the direct drive signal to the gate of the graphene parameter resonator under test. It also includes a DC voltage source, which is connected to the gate DC signal terminal of the graphene parameter resonator under test, and the DC voltage source is used to apply a bias voltage to the gate of the graphene parameter resonator under test.

9. The vibration phase bit encoding test device based on a graphene parametric resonator according to claim 8, characterized in that, The reflective assembly includes two mirrors, which are symmetrically placed and are used to transmit the laser beam to the polarization beam splitter in a direction opposite to the initial emission direction after two 90° emission.

10. The vibration phase bit encoding test device based on a graphene parametric resonator according to claim 8, characterized in that, The waveform expression of the reference signal is as follows: ; in, Indicates the direct drive angular frequency. Indicates the amplitude of the reference signal waveform. Indicates time, This represents the phase difference between the direct drive signal and the parameter excitation signal.

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