A method and device for measuring random telegraph noise

Abstract

The present invention provides a random telegraph noise measurement method and device, the method comprising the following steps: applying random telegraph noise to atoms in a radio frequency field and a static magnetic field to generate a magnetic resonance signal with two magnetic resonance peaks; calculating the amplitude and phase flip frequency of the random telegraph noise according to the width from the magnetic resonance peak to the center and the resonance point height of the magnetic resonance signal. The accuracy of the present invention is not limited by the sampling rate, the data processing is simple, and the traceability is possible.

Description

Technical Field

[0001] The invention belongs to the technical field of random telegraph noise, and in particular relates to a random telegraph noise measurement method and device. Background Art

[0002] The existing random telegraph noise measurement methods are mainly the following: 1) Direct time domain sampling analysis method. This method first samples the noise voltage signal of the sample, assuming that the noise only contains random telegraph noise signals and Gaussian background noise, and then calculates the discrimination threshold according to the characteristics of random telegraph noise signals and Gaussian noise, judges the sampled voltage, and then obtains its random telegraph noise signal. This method is restricted by the sampling frequency. 2) Time Lag Plot (TLP) method. TLP can extract random telegraph noise signals by simply drawing points on the xy plane, where x is set to the i-th sampling data and y is set to the next sampling data. Its related parameters are measured by statistical methods. However, the measurement accuracy of this method is also affected by the sampling frequency. 3) Weighted Time Lag Plot (W-TLP) method. W-TLP adds a weight coefficient on the basis of TLP, which can extract the time parameters of random telegraph noise with multi-level values. 4) Energy equivalence method. This method uses the classical modal decomposition algorithm to perform modal decomposition on the low-frequency noise of the device, and uses the energy equivalent method to accurately locate the pulse rise / fall edge time of the random telegraph noise signal, thereby measuring its time parameters. However, this method also requires sampling of the random telegraph noise, which is limited by the sampling rate.

[0003] In summary, the measurement of random telegraph noise parameters at home and abroad mainly uses statistical methods, which have many sampling points, cumbersome processing and large errors. Summary of the invention

[0004] The purpose of the present invention is to solve the shortcomings of the above-mentioned background technology and provide a random telegraph noise measurement method and device, the accuracy of which is not limited by the sampling rate, the data processing is simple, and the data can be traced.

[0005] The technical solution adopted by the present invention is: a method for measuring random telegraph noise, comprising the following steps:

[0006] applying random telegraph noise to atoms in a radio frequency field and a static magnetic field to generate a magnetic resonance signal with two magnetic resonance peaks;

[0007] The amplitude and phase reversal frequency of the random telegraph noise are calculated based on the width from the magnetic resonance peak to the center and the height of the resonance point of the magnetic resonance signal.

[0008] In the above technical solution, the coupled Rabi frequency of the random telegraph noise is calculated based on the frequency difference and resonance point height of the two magnetic resonance peaks of the magnetic resonance signal; the amplitude of the random telegraph noise is calculated based on the mapping relationship between the coupled Rabi frequency and the amplitude of the random telegraph noise.

[0009] In the above technical solution, the width from the magnetic resonance peak to the center is used to characterize the mathematical relationship between the coupled Rabi frequency and phase flip frequency of the random telegraph noise and the frequency of the radio frequency field; the height of the magnetic resonance resonance point is used to characterize the mathematical relationship between the coupled Rabi frequency of the random telegraph noise and the line width of the atomic ground state hyperfine structure.

[0010] In the above technical solution, the coupled Rabi frequency of random telegraph noise is calculated using the following formula: a and the phase flip frequency γ:

[0011] ;

[0012] Among them, Ω RF represents the frequency of the radio frequency field; Γ represents the line width of the atomic ground state hyperfine structure; d represents the width from the magnetic resonance peak to the center; and h represents the height of the resonance point.

[0013] In the above technical solution, a radio frequency field and a static magnetic field are first applied to the atoms to generate a magnetic resonance signal; then the magnetic resonance state of the atoms is maintained, and random telegraph noise is applied to the atoms to make the magnetic resonance signal generate two magnetic resonance peaks.

[0014] In the above technical solution, after applying random telegraph noise to the atoms, the amplitude of the radio frequency field is adjusted until two magnetic resonance peaks appear in the magnetic resonance signal.

[0015] The present invention also provides a random telegraph noise measuring device, which is used to implement the method described in the above technical solution, and includes a first coil, a second coil, an atomic gas chamber, a laser, a photodetector and an oscilloscope; wherein the first coil and the second coil are arranged perpendicular to each other in the atomic gas chamber; wherein the first coil is used to generate a static magnetic field and receive random motor noise, and the second coil is used to generate a radio frequency field; the atoms in the atomic gas chamber generate a magnetic resonance signal with two magnetic resonance peaks under the action of the radio frequency field, the static magnetic field and the random motor noise; the light generated by the laser passes through the atomic gas chamber and is collected by the photodetector; the oscilloscope displays the signal collected by the photodetector; the amplitude and phase flip frequency of the random telegraph noise are calculated based on the width from the magnetic resonance peak to the center and the resonance point height of the magnetic resonance signal displayed by the oscilloscope.

[0016] The above technical solution also includes a magnetic shielding barrel; the atomic gas chamber is arranged in the magnetic shielding barrel; an antenna for coupling random telegraph noise is arranged outside the magnetic shielding barrel; and the antenna is electrically connected to the first coil.

[0017] In the above technical solution, a static magnetic field is generated by providing a DC power supply to the first coil; and a radio frequency field is generated by providing a square wave sine signal as a modulation signal to the second coil.

[0018] In the above technical solution, the first coil and the second coil are Helmholtz coils of the same size and the same number of turns.

[0019] The beneficial effects of the present invention are as follows: the present invention provides a random telegraph noise measurement method based on noise-assisted multiphoton effect, which does not require noise sampling, and the measurement accuracy is not limited by the sampling frequency. It only needs to record the magnetic resonance spectrum under random telegraph noise excitation, and use the magnetic resonance peak-center distance and the resonance point height to determine the random telegraph noise amplitude and phase flip frequency parameters. The data processing is simple, the traceability can be found, and the measurement accuracy is greatly improved. Although the random telegraph noise itself is a two-value time-varying signal, the random telegraph noise will make the magnetic resonance system reach a new steady state (dynamic balance) after coupling with the atomic magnetic resonance. The measured result is the steady-state DC component. The DC spectrum component will be split into two peaks due to the influence of the telegraph noise, so there is no need to sample the random telegraph noise.

[0020] Furthermore, the present invention derives the Hamiltonian of the interaction between the atomic hyperfine structure and the radio frequency field and the noise field, and gives the analytical form of the transmission spectrum, thereby determining the mathematical relationship between the random telegraph noise parameters represented by the width from the magnetic resonance peak to the center and the height of the magnetic resonance resonance point and the radio frequency field and atomic parameters, and then establishes a random telegraph noise calculation formula. The user substitutes the reading result of the oscilloscope into the random telegraph noise calculation formula to obtain the parameter information of the random telegraph noise, thereby improving the calculation efficiency of the random telegraph noise while ensuring the calculation accuracy.

[0021] Furthermore, the present invention firstly generates magnetic resonance signals by applying radio frequency fields and static magnetic fields to atoms, and then applies the motor telegraph noise to be measured to generate a double peak phenomenon, thereby ensuring that users can clearly observe the state of the magnetic resonance signals, ensuring the orderliness of the measurement process, and improving measurement efficiency and accuracy.

[0022] Furthermore, the present invention continuously adjusts the radio frequency field amplitude until two magnetic resonance peaks clearly appear in the magnetic resonance signal, and then calculates the information of the random telegraph noise according to the parameters of the magnetic resonance peaks, thereby effectively ensuring the measurement accuracy.

[0023] Furthermore, the present invention provides a random telegraph noise measuring device, which can effectively practice a random telegraph noise measuring method, realize random telegraph noise measurement through a physical device, has strong operability, and can ensure measurement accuracy during use.

[0024] Furthermore, the present invention uses a coupling antenna to collect the random telegraph noise to be measured outside the magnetic shielding barrel, ensuring that the mixed background noise is less; during the measurement process, the magnetic shielding barrel can effectively shield other irrelevant background noise outside the barrel and the influence of the magnetic field. The mixed background Gaussian noise is no longer directly sampled and directly affects the measurement results like other methods, but only affects the sensitivity of the magnetic resonance system and other related factors, weakening the influence of background noise on the random telegraph noise measurement results. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 A schematic diagram of a method flow chart of an embodiment;

[0026] Figure 2 This is a schematic diagram of a random telegraph noise field;

[0027] Figure 3 is a schematic diagram of a magnetic resonance signal of an embodiment;

[0028] Figure 4 A schematic diagram of a device system of an embodiment;

[0029] Figure 5 An image showing the relationship between the radio frequency signal and the Rabi frequency in the embodiment;

[0030] Figure 6 This is an image of the relationship between the random telegraph noise amplitude and the noise field coupling Rabi frequency in the embodiment;

[0031] Figure 7 Graph showing the results of a random telegraph noise test in the embodiment. DETAILED DESCRIPTION

[0032] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments to facilitate a clear understanding of the present invention, but they do not constitute a limitation on the present invention.

[0033] Example 1

[0034] like Figure 1 As shown, the present invention provides a random telegraph noise measurement method, comprising the following steps:

[0035] applying random telegraph noise to atoms in a radio frequency field and a static magnetic field to generate a magnetic resonance signal with two magnetic resonance peaks;

[0036] The amplitude and phase reversal frequency of the random telegraph noise are calculated based on the width from the magnetic resonance peak to the center and the height of the resonance point of the magnetic resonance signal.

[0037] Specifically, the coupled Rabi frequency of the random telegraph noise is calculated based on the frequency difference of the two magnetic resonance peaks of the magnetic resonance signal and the height of the resonance point; and the amplitude of the random telegraph noise is calculated based on the mapping relationship between the coupled Rabi frequency and the amplitude of the random telegraph noise. The mapping relationship between the coupled Rabi frequency and the amplitude of the random telegraph noise is a known mathematical knowledge, and the mapping relationship between the coupled Rabi frequency and the amplitude of different random telegraph noises is consistent.

[0038] Preferably, random telegraph noise is generated by the technical solution of Chinese patent "202311412776X A method and system for generating random telegraph noise", and the coupled Rabi frequency and amplitude mapping relationship of the random telegraph noise is determined and used for subsequent calculations.

[0039] Specifically, the atoms can be quantum systems that can constitute magnetic resonance, including quantum ensembles (alkali metal atoms such as rubidium, cesium, potassium, etc., cold atoms), solid-state devices (artificial atomic NV color centers, etc.).

[0040] Specifically, the width from the magnetic resonance peak to the center is used to characterize the mathematical relationship between the coupled Rabi frequency and phase flip frequency of the random telegraph noise and the frequency of the radio frequency field; the height of the magnetic resonance resonance point is used to characterize the mathematical relationship between the coupled Rabi frequency of the random telegraph noise and the line width of the atomic ground state hyperfine structure, as shown in the following formula:

[0041] ;

[0042] Where a is the coupled Rabi frequency of random telegraph noise, γ is the phase flip frequency, Ω RF represents the frequency of the radio frequency field; Γ represents the line width of the atomic ground state hyperfine structure; d represents the width from the magnetic resonance peak to the center; and h represents the height of the resonance point.

[0043] The reasoning process of the above formula principle is as follows:

[0044] This specific embodiment derives the Hamiltonian of the interaction between the Fg=4 hyperfine structure of the cesium atom and the radio frequency field and the noise field, and gives the analytical form of the transmission spectrum, thereby deriving the above formula.

[0045] Under the influence of magnetic field B, the torque acting on the atom is in, is the atomic magnetic moment. In the small magnetic field limit, it can be assumed that the atomic magnetic moment and The component of the angular momentum moment L perpendicular to B is at the Larmor frequency Around Precession, where is the gyromagnetic ratio. When light passes through an atomic medium and interacts with it, an exchange of angular momentum occurs between the atoms and the light field; in turn, this causes the atomic angular momentum state to affect the angular momentum state of the light field. In this way, the atomic angular momentum precession can be observed by changes in the polarization and intensity of the laser light interacting with the atoms, thereby achieving optical measurement of the hyperfine structure angular momentum Larmor precession. The exchange of angular momentum between the atomic medium and the light field enables the optical detection of the Larmor precession frequency, and likewise the induction of atomic polarization through the optical pumping process. Optical pumping refers to the process in which a photon absorbed by an atom transfers its angular momentum to the atom, thereby producing polarization in both the ground state and the excited state. The ground state spin polarization is achieved by the reduction of the population of a selected Zeeman sublevel and the refilling of the Zeeman sublevel by the spontaneous emission process of the excited state.

[0046] In order to obtain the magnetic resonance spectroscopy information induced by the noise-assisted multiphoton process, the spatial distribution of the physical field is constructed: the magnetic field in the z direction is ,in In order to make atoms produce Zeeman splitting static magnetic field, is the noise magnetic field generated by the random telegraph noise source; the magnetic field in the x direction is , is the alternating coherent magnetic field.

[0047] Hamiltonian H in spherical harmonic representation B for:

[0048] ;

[0049] in is the angular momentum component in the covariant spherical harmonic representation, is the magnetic field component in the inverse spherical harmonic representation, g F is the Lande factor; B total It is the sum of static magnetic field, radio frequency field and noise field, that is, the total magnetic field; μ B is the Bohr magneton.

[0050] Therefore, the Hamiltonian H0 for the interaction between the total magnetic field and the ground state atomic hyperfine structure is:

[0051] ;

[0052] Mode middle , , .

[0053] coefficient The static magnetic field The resulting hyperfine Zeeman splitting Rabi frequency, Ω1 is the RF field Rabi frequency.

[0054] Hamiltonian It is a radio frequency field and noise field Hamiltonian for the interaction with atoms. RF field Frequency Larmor precession frequency Resonance.

[0055] Introducing unitary transformation The system Hamiltonian Rotate into the interaction representation, that is:

[0056] ;

[0057] make , we can calculate

[0058] .

[0059] Atomic spin polarization is generated by optical pumping through one or more cycles of light absorption-emission, transferring angular momentum from the beam to the atoms. , the atomic ensemble with angular momentum F can be expressed by the density operator of Matrix elements Description, where represents other quantum numbers besides F and M, which together with F and M explicitly describe the angular momentum system. M' represents other quantum numbers other than M; in addition, the density operator can be decomposed into:

[0060] ;

[0061] Based on the irreducible spherical tensor operator, we can get:

[0062] ;

[0063] Among them, T k,q represents the irreducible tensor of the q-component of the k-order irreducible tensor, k represents the order of the irreducible tensor, q represents the q-component of the k-order irreducible tensor; C represents the Clebsch–Gordan coefficient, and its subscripts and subscripts are defined in the same way as above; the atomic multipole moment of the q-component of the k-order irreducible tensor Contains the matrix elements Same information. Hermitian conjugation condition Convert to . Longitudinal multipole moment The total energy level of the magneton The linear superposition of Depend on The coherence density matrix element The complete system description consists of the matrix elements Same number of multipole moments In systems with large angular momentum F, the actual number of parameters required to fully determine the polarization of the system can become very large. However, by taking into account the symmetries of the polarimetric medium, the number of required parameters can be greatly reduced. For example, if the system remains unchanged when rotated about the quantization axis, then all transverse moments If the system remains unchanged under reflection in the perpendicular z plane, then all multipole moments of odd order k will disappear.

[0064] To further reveal the physical origin of the noise-assisted multiphoton effect, the total angular momentum state Represent the atomic system and assume .Mode The irreducible spherical harmonic tensor operator introduced in Obey the regular exchange relationship ( ), then the covariant component of the hyperfine structure angular momentum F in the spherical harmonic representation satisfies the following commutation relation:

[0065] ;

[0066] The parameters is the Clebsch-Gordan coefficient. The dynamic evolution of is described by the Liouville equation, namely:

[0067] ;

[0068] The operator Describes the relaxation process of the system, the density matrix Describe the equilibrium state of the system. Substitution And using the commutation relation ,make , the general evolution equation of atomic multipole moment is obtained as:

[0069] .

[0070] Phenomenologically adding the atomic multipole moment relaxation process, we get:

[0071] ;

[0072] here is the relaxation coefficient of the atomic multipole moment of the q-component of the k-th order irreducible tensor. When k=1, it corresponds to the orientation polarization atomic multipole moment evolution equation studied in this paper. When , the steady-state solution of the atomic multipole moment of the system can be given. q,0 represents the Kronecker symbol; when q=0, δ q,0 =1; when q≠0, δ q,0 =0.

[0073] Considering the properties of random telegraph noise, its dynamics can be completely described by the Chapman-Kolmogorov-Smoluchowski (CKS) equation: :

[0074] ;

[0075] in, is the frequency of the random telegraph noise at time t changing state in the interval (t, t+dt), function Indicates that the initial state is Under the condition of, jump to the state in the interval (t, t+dt) The conditional probability of a0 is the initial state and t0 is the initial time.

[0076] For the two-state equal probability telegraph noise used in the embodiment, we have:

[0077] .

[0078] Combined The CSK equation shown is:

[0079] .

[0080] Therefore, the formula It can be expressed as:

[0081] ;

[0082] in, and are the two-state phase reversal frequencies of random telegraph noise, and are the field sizes corresponding to the two states of the random telegraph noise field.

[0083] like Figure 2 Injection and Satisfaction relationship .when and When , the corresponding analytical solution is:

[0084] ;

[0085] in,

[0086] ;

[0087] in, is the atomic ground state hyperfine structure linewidth (in kHz), is the Rabi frequency of the coupling between the noise field and the system (in kHz), is the detuning of the RF field from the Larmor precession frequency, is the phase flip frequency of random telegraph noise (in krad / s). The noise field coupling Rabi frequency a is 1.5kHz, and the random telegraph noise phase flip frequency γ is 3krad / s. The above equation is simulated, and the simulated magnetic resonance signal image is as follows: Figure 3 shown. Figure 3 The width d from the mid-peak to the center and the resonance point The height h of the magnetic resonance peak can be expressed as:

[0088] ;

[0089] Mode middle, For RF field size.

[0090] Specifically, during use, the present invention first applies a radio frequency field and a static magnetic field to the atoms to generate a magnetic resonance signal; wherein the frequencies of the radio frequency field and the static magnetic field are the same, and their magnitudes are determined based on the atomic properties to ensure that a magnetic resonance state can be achieved, that is, the collected magnetic resonance signal can be clearly displayed by an oscilloscope.

[0091] The magnetic resonance state of the atoms is then maintained and random telegraph noise is applied to the atoms, causing the magnetic resonance signal displayed by the oscilloscope to produce two magnetic resonance peaks.

[0092] Since random telegraph noise itself is a two-value time-varying signal, the coupling of random telegraph noise with atomic magnetic resonance will cause the magnetic resonance system to reach a new steady state (dynamic equilibrium). The measured result is the steady-state DC component. The DC spectral component will be split into two peaks due to the influence of telegraph noise. The amplitude and flipping frequency of the telegraph noise can be calculated by measuring the frequency difference between the two peaks and the amplitude of the centers of the two peaks.

[0093] Preferably, applying random telegraph noise to the atoms may cause the magnetic resonance signal displayed by the oscilloscope to be unclear, so it is necessary to gradually increase the RF field amplitude according to the set step size until two magnetic resonance peaks appear in the magnetic resonance signal, that is, an obvious double peak phenomenon can be observed through the oscilloscope.

[0094] Example 2

[0095] like Figure 4 As shown, the present invention provides a random telegraph noise measurement device, which is used to implement the method described in Example 1, including a first coil, a second coil, an atomic gas chamber, a laser, a photodetector and an oscilloscope; wherein the first coil and the second coil are arranged perpendicular to each other in the atomic gas chamber; wherein the first coil is used to generate a static magnetic field and receive random motor noise, and the second coil is used to generate a radio frequency field; the atoms in the atomic gas chamber generate a magnetic resonance signal with two magnetic resonance peaks under the action of the radio frequency field, the static magnetic field and the random motor noise; the light generated by the laser passes through the atomic gas chamber and is collected by the photodetector; the oscilloscope displays the signal collected by the photodetector; according to the width from the magnetic resonance peak to the center and the resonance point height of the magnetic resonance signal displayed by the oscilloscope, the amplitude and phase flip frequency of the random telegraph noise are calculated.

[0096] Specifically, it also includes a magnetic shielding barrel; the atomic gas chamber is arranged in the magnetic shielding barrel; an antenna for coupling random telegraph noise is arranged outside the magnetic shielding barrel; and the antenna is electrically connected to the first coil.

[0097] Specifically, a static magnetic field is generated by providing a direct current power supply to the first coil; and a radio frequency field is generated by providing a square wave sine signal as a modulation signal to the second coil.

[0098] Preferably, the static magnetic field is generated by a precision current source generating a DC signal and adding it to the first coil, and the static magnetic field is controlled by controlling the magnitude of the DC signal. The radio frequency field is generated by a signal source generating an alternating signal and adding it to the second coil, and the radio frequency field is controlled by controlling the frequency and amplitude of the alternating signal.

[0099] In this embodiment, an anti-relaxation vacuum cesium atomic gas chamber is used, which has a diameter of 28 mm, a length of 30 mm and a layer of paraffin on the inner wall. The cesium atomic gas chamber is isolated from the ambient magnetic field by four layers of high magnetic permeability metal shielding layers. The coils in the magnetic shielding barrel have the same size and the same number of turns in the x and z directions. Static magnetic field A precision current source (Keysight B2912A) drives a set of two pairs of Helmholtz coils in the z direction, i.e., the first coil. The RF field is generated by a signal source driving a set of two pairs of Helmholtz coils in the x direction, i.e., the second coil.

[0100] The laser beams used to pump and probe the atomic gas cell are generated by an 895 nm DBR laser that locks the laser to the hyperfine structure via saturation absorption spectroscopy. PBS is followed by a 1 / 4 glass slide to prepare circularly polarized light. After passing through the 1 / 4 glass slide, the purity of circular polarization is greater than 99%. The light that passes through the atomic gas chamber is received by the photodetector PD and converted into an electrical signal and then transmitted to the oscilloscope (SDS2504X HD). The spectrum displayed by the oscilloscope is analyzed by scanning the RF frequency.

[0101] First, we conducted a Rabi frequency measurement experiment to determine the relationship between the amplitude of the RF field generated by the Helmholtz coil driven by the AC signal output by the signal source and the Rabi frequency. The high-precision current source outputs a DC of 136.5 mA to drive a pair of Helmholtz coils in the z direction to generate a static magnetic field. , so that the Larmor precession frequency is The signal source outputs a sine signal with a frequency of 50kHz, driving a pair of Helmholtz coils in the x direction, causing the atoms in the gas chamber to oscillate Rabi. The signal output by the PD is observed on an oscilloscope. Since the signal is an attenuated signal, in order to observe the free evolution of the atoms, the signal source output is changed to a modulated wave. The signal source generates an amplitude modulated wave with a modulation frequency of 10Hz, the modulation signal is a square wave, and the carrier is a sine signal with a frequency of 50kHz.

[0102] Use an oscilloscope to observe the photoelectric detection PD output signal, change the carrier amplitude, record the frequency of the corresponding attenuated signal, and obtain the relationship between the RF signal amplitude and the Rabi frequency, such as Figure 5 As shown. Among them, the straight line is the fitting result, and the points with error bars are actual data. The fitting result is:

[0103]

[0104] in is the RF field size (in kHz), is the RF signal amplitude (in V).

[0105] In order to verify the accuracy of the present invention, the parameters of the self-made random telegraph noise are obtained by the present invention.

[0106] First, the random telegraph noise Rabi frequency experimental measurement is carried out. The random telegraph noise source outputs a random telegraph noise signal, and the noise magnetic field generated by the Helmholtz coil is driven by an external coupling antenna, so as to determine the corresponding relationship between the noise magnetic field-atomic system coupling Rabi frequency and the amplitude of the random telegraph noise signal. The precision current source outputs a DC 273mA to drive a pair of Helmholtz coils in the z direction to generate a static magnetic field. , so that the Larmor precession frequency is The signal source outputs a swept frequency signal with a center frequency of 100kHz and an amplitude of 0.2V, driving a pair of Helmholtz coils in the x direction to generate a radio frequency field. , according to the formula It can be seen that the corresponding RF field size , RF field frequency .

[0107] Random telegraph noise source output flip frequency , random telegraph noise with an offset frequency of 0, driving the Helmholtz coil in the z direction to generate a noise field . Change the amplitude of random telegraph noise, observe the magnetic resonance signal on the oscilloscope, record the distance between the magnetic resonance peak and the center, and use the formula The coupled Rabi frequency and phase flip frequency of the random telegraph noise are calculated, and then the relationship between the amplitude of the random telegraph noise and the size of the noise field is plotted, such as Figure 6 shown.

[0108] Keep the following parameters of random telegraph noise unchanged: Random telegraph noise amplitude is 1.1Vpp, and the phase reversal frequency is , the offset frequency is .

[0109] The random telegraph noise drives the Helmholtz coil in the z direction to generate a noise field , use an oscilloscope to record the magnetic resonance phenomenon, record the double peak distance d and the resonance point height h of the magnetic resonance peak. According to the formula The noise field coupling Rabi frequency a is calculated to be 3.3863kHz, the phase flip frequency γ is 3.17krad / s, and the error is 5.7%. Figure 6 The relationship between the random telegraph noise amplitude and the noise field coupling Rabi frequency determines that the corresponding random telegraph noise amplitude ΔU is 1.108V, with an error of 0.7%. The test results are as follows Figure 7 As shown, it can be seen that the experimental and theoretical magnetic resonance peaks are in good agreement.

[0110] The contents not described in detail in this specification belong to the prior art known to professional and technical personnel in this field.

Claims

1. A method for measuring random telegraph noise, characterized in that: The following steps are involved: First, a radio frequency field and a static magnetic field are applied to the atoms to generate magnetic resonance signals; Maintaining the magnetic resonance state of the atoms, applying random telegraph noise to the atoms, and adjusting the amplitude of the radio frequency field until two magnetic resonance peaks appear in the magnetic resonance signal; According to the frequency difference and resonance point height of the two magnetic resonance peaks of the magnetic resonance signal, the coupled Rabi frequency and the phase flip frequency of the random telegraph noise are calculated; According to the mapping relationship between the coupled Rabi frequency and the amplitude of the random telegraph noise, the amplitude of the random telegraph noise is calculated; The coupled Rabi frequency of random telegraph noise is calculated using the following formula: a and the phase flip frequency γ: ； Among them, Ω RF represents the frequency of the radio frequency field; Γ represents the line width of the atomic ground state hyperfine structure; d represents the width from the magnetic resonance peak to the center; and h represents the height of the resonance point.

2. A random telegraph noise measuring device, characterized in that: The method for implementing the method of claim 1 comprises a first coil, a second coil, an atomic gas chamber, a laser, a photodetector and an oscilloscope; wherein the first coil and the second coil are arranged perpendicularly to each other in the atomic gas chamber; wherein the first coil is used to generate a static magnetic field and receive random motor noise, and the second coil is used to generate a radio frequency field; the atoms in the atomic gas chamber generate a magnetic resonance signal with two magnetic resonance peaks under the action of the radio frequency field, the static magnetic field and the random motor noise; the light generated by the laser passes through the atomic gas chamber and is collected by the photodetector; the oscilloscope displays the signal collected by the photodetector; the amplitude and phase flip frequency of the random telegraph noise are calculated based on the width from the magnetic resonance peak to the center and the resonance point height of the magnetic resonance signal displayed by the oscilloscope.

3. A random telegraph noise measuring device as claimed in claim 2, characterized in that: It also includes a magnetic shielding barrel; the atomic gas chamber is arranged in the magnetic shielding barrel; an antenna for coupling random telegraph noise is arranged outside the magnetic shielding barrel; the antenna is electrically connected to the first coil.

4. A random telegraph noise measuring device as claimed in claim 3, characterized in that: A static magnetic field is generated by providing a direct current power supply to the first coil; and a radio frequency field is generated by providing a square wave sine signal as a modulation signal to the second coil.

5. A random telegraph noise measuring device as claimed in claim 3, characterized in that: The first coil and the second coil are Helmholtz coils of the same size and the same number of turns.

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