Quantum current sensor capable of reducing microwave interference and current detection method

Abstract

The invention provides a quantum current sensor capable of reducing microwave interference and a current detection method. The sensor comprises a plurality of solid-state spinning color center detection modules, a laser source, a microwave source and a processing module, each solid-state spinning color center detection module is used for sensing a magnetic field generated after a conductor to be detected is electrified, receiving laser transmitted by the laser source, receiving modulated microwaves transmitted by the microwave source, collecting and detecting fluorescent light generated by the solid-state spinning color center under the action of the laser, the modulated microwaves and the magnetic field, and outputting a detection signal to the processing module; the modulation frequencies of microwaves transmitted by the microwave source to every two solid-state spinning color center detection modules are different; and the processing module is used for collecting the detection signal, demodulating the detection signal to obtain demodulated data, calculating a current value according to the demodulated data, and transmitting a frequency modulation signal to the microwave source. Therefore, during demodulation, the reference signal with the corresponding modulation frequency is used for demodulation, a correct fluorescence signal can be demodulated, microwave interference caused by other probes at a short distance can be reduced, and the measurement accuracy is further improved.

Description

Technical Field

[0001] This invention relates to the field of quantum sensing, and in particular to a quantum current sensor and current detection method that reduces microwave interference. Background Technology

[0002] Solid-state spin color center systems are important physical systems for realizing quantum precision measurement. Taking diamond NV color centers as an example, magnetic field measurements using them have advantages such as wide temperature range, high precision, and large range, providing a new and effective way to solve the problem of current measurement in power systems.

[0003] To improve the signal-to-noise ratio and avoid 1 / f noise, existing quantum current sensors employ a modulation signal of a certain frequency added to the microwave. Since the microwave frequency oscillates in a sinusoidal or square wave manner, the fluorescence generated by the NV color center near the resonance absorption peak will also oscillate at a corresponding frequency. After demodulation, the first-order differential spectrum, i.e., the demodulation curve, can be obtained. The modulated microwave frequency can be expressed by the following formula: ,in, It is an unmodulated frequency. It is the modulation depth. It is the modulation frequency. This is the modulation phase. The AC signal used for demodulation in the fluorescence signal generated by this modulated microwave is... , The oscillation amplitude of the fluorescence signal. For fluorescence phase. Using a reference signal. Mixing with the fluorescence signal, since the frequency of the reference signal is the same as that of the fluorescence signal, the result after mixing is: Then, through low-pass filtering, we can obtain: ,adjust , making ,get: ,because If it is known, then it can be extracted. .

[0004] In practical applications, multiple solid-state spin center quantum probes are often placed on the outer circumference of the conductor under test. When these quantum probes are close together and operating simultaneously, the microwaves radiated by the antennas of adjacent probes can interfere with each other. For example... Figure 2 As shown, when the resonant frequency of quantum probe A is At that time, the microwaves generated by the adjacent quantum probe B... The oscillations occur in the vicinity, and the oscillation frequency is the modulation frequency. ,when and When the difference is not significant, such as Figure 2If both frequencies are within the same resonance peak, or within two different resonance peaks, the microwaves generated by the quantum probe B antenna will cause a change in the fluorescence signal on the quantum probe A. When the fluorescence signals are in phase, the AC signals used for demodulation in the fluorescence signal generated by the same quantum probe are superimposed. Finally, the demodulation result is obtained Mixed with Interference with other quantum probes can introduce more interference signals, leading to errors in the acquisition of the resonant frequency and consequently introducing errors into the measurement. Summary of the Invention

[0005] In view of the shortcomings of the prior art described above, the purpose of this invention is to provide a quantum current sensor and current detection method that reduces microwave interference, in order to solve the problem that microwave interference exists when multiple quantum probes are close to each other and work simultaneously, introducing errors into the measurement.

[0006] To achieve the above and other related objectives, a first aspect of the present invention provides a quantum current sensor for reducing microwave interference, comprising: multiple solid-state spin center detection modules, a laser source, a microwave source, and a processing module; each solid-state spin center detection module is used to sense the magnetic field generated after a current is passed through the conductor under test, receive laser light from the laser source, and receive modulated microwave light transmitted from the microwave source, and collect and detect the fluorescence generated by the solid-state spin center under the action of the laser, modulated microwave light, and magnetic field, and output a detection signal to the processing module; the microwave source transmits microwaves with different modulation frequencies to every two solid-state spin center detection modules; the processing module is used to acquire the detection signal, demodulate the AC signal therein using a reference signal with a corresponding modulation frequency to obtain demodulated data, calculate the magnetic field strength value and / or current value based on the demodulated data, and also transmit a frequency modulation signal to the microwave source.

[0007] Furthermore, each solid-state spin center detection module includes a quantum probe containing a solid-state spin center, a microwave antenna, and a detection module; the microwave antenna receives modulated microwaves transmitted from a microwave source and radiates the modulated microwaves to the quantum probe, which is also used to sense magnetic fields and receive laser irradiation; the detection module is used to collect and detect fluorescence and output detection signals to the processing module.

[0008] Furthermore, the distance between any two adjacent quantum probes is no more than 10 cm.

[0009] Furthermore, the modulation frequency difference of the microwaves transmitted to each of the two adjacent solid-state spin center detection modules is not less than 1 kHz, and each modulation frequency is not greater than the maximum modulation frequency that the spin center can accept.

[0010] Furthermore, multiple solid-state spin center detection modules are arranged at intervals on a circle centered on the cross-section of the conductor under test, or located on one or both sides of the conductor under test.

[0011] Furthermore, the processing module adjusts the frequency of the modulated microwave radiated by the microwave source according to the demodulated data and through a closed-loop control algorithm to obtain the resonant frequency corresponding to the magnetic field, and calculates the magnetic field strength value and the current value according to the resonant frequency.

[0012] Furthermore, the detection module includes a fluorescence detection module, which is used to collect the fluorescence generated by the detection quantum probe, output a fluorescence electrical signal, and transmit the fluorescence electrical signal as a detection signal to the processing module.

[0013] Furthermore, the detection module includes a fluorescence detection module, a laser detection module, and a differential circuit. The laser transmitted from the laser source to each solid-state spin center detection module is split into two paths. One path is transmitted to the quantum probe, where the fluorescence detection module collects the fluorescence generated by the quantum probe and outputs a fluorescence electrical signal. The other path is transmitted to the laser detection module and converted into a laser electrical signal. The differential circuit receives the fluorescence electrical signal and the laser electrical signal, performs differential processing on them, and transmits the resulting differential electrical signal as a detection signal to the processing module.

[0014] Furthermore, the solid-state spin color center is one of the following: diamond nitrogen vacancy color center, diamond germanium vacancy color center, diamond silicon vacancy color center, silicon carbide silicon-carbon double vacancy color center, silicon carbide silicon vacancy color center, and hexagonal boron nitride boron vacancy color center.

[0015] To achieve the above and other related objectives, a second aspect of the present invention provides a quantum current detection method for reducing microwave interference, comprising: placing a plurality of quantum probes containing solid-state spin centers in a magnetic field generated by the current to be measured; irradiating each quantum probe with a laser and radiating modulated microwaves; wherein the modulation frequency of the microwaves transmitted to each pair of quantum probes is different; collecting the fluorescence generated by the probes to obtain a detection signal; demodulating the AC signal therein using a reference signal with a corresponding modulation frequency to obtain demodulated data; and calculating the magnetic field strength value and / or current value based on the demodulated data.

[0016] As described above, the quantum current sensor and current detection method for reducing microwave interference of the present invention have the following beneficial effects: For multiple solid-state spin center detection modules, the modulation frequency of the microwaves transmitted to each pair of solid-state spin center detection modules is different. During demodulation, a reference signal with the corresponding modulation frequency is used for demodulation, which can demodulate the correct fluorescence signal. This can reduce the microwave mutual interference generated when multiple solid-state spin center detection modules work simultaneously at close range, thereby improving the accuracy of measurement. Attached Figure Description

[0017] Figure 1 The diagram shown is a schematic representation of the quantum current sensor structure of the present invention.

[0018] Figure 2 The diagram shows the fluorescence changes caused by microwave interference between two probes at close range;

[0019] Figure 3 The diagram shown is a structural schematic of a detection module;

[0020] Figure 4 This is a schematic diagram of another structure of the detection module;

[0021] Figure 5 The graph shown is the demodulation curve obtained by microwave sweep frequency method for ODMR measurement of diamond NV color centers.

[0022] Component labeling: 1—Solid-state spin center detection module; 11—Quantum probe; 12—Microwave antenna; 13—Detection module; 131—Filter; 132—First photodetector; 133—First voltage converter circuit; 134—Differential circuit; 135—Second photodetector; 136—Second voltage converter circuit; 2—Laser source; 3—Microwave source; 4—Processing module; 41—Analog-to-digital converter; 42—Demodulation module; 5—Conductor under test. Detailed Implementation

[0023] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that, unless otherwise specified, the following embodiments and features described therein can be combined with each other.

[0024] It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of the present invention. Therefore, the illustrations only show the components related to the present invention and are not drawn according to the actual number, shape and size of the components in the actual implementation. In the actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0025] Example 1: As Figure 1As shown, this embodiment provides a quantum current sensor with reduced microwave interference, including: multiple solid-state spin center detection modules 1, a laser source 2, a microwave source 3, and a processing module 4; each solid-state spin center detection module 1 is used to sense the magnetic field generated after current is passed through the conductor 5 under test, receive laser light from the laser source 2, and receive modulated microwave light transmitted from the microwave source 3, and collect and detect the fluorescence generated by the solid-state spin center under the action of laser light, modulated microwave light, and magnetic field, and output the detection signal to the processing module 4; the microwave source 3 transmits microwaves with different modulation frequencies to every two solid-state spin center detection modules 1; the processing module 4 is used to collect the detection signal, demodulate the AC signal with a reference signal with a corresponding modulation frequency to obtain demodulated data, calculate the magnetic field strength value and / or current value based on the demodulated data, and also transmit the frequency modulation signal to the microwave source 3.

[0026] In this embodiment, microwaves with different modulation frequencies are delivered to multiple solid-state spin center detection modules. Taking two solid-state spin center detection modules as an example, the applied microwave frequencies are as follows: and In demodulation processing, the AC signals generated by two microwaves with different modulation frequencies on the same solid-state spin center detection module are superimposed. For the superimposed signal generated by the first solid-state spin center detection module, using Demodulating the signal as a reference signal can yield the demodulated signal. For the superimposed signal generated by the second solid-state spin center detection module, using Demodulating the signal as a reference signal can yield the demodulated signal. Similarly, this can be applied to the superposition of AC signals generated by more than two microwaves with different modulation frequencies on the same solid-state spin center detection module. Therefore, it is evident that using a reference signal with the corresponding modulation frequency for demodulation can correctly demodulate the fluorescence signal, reducing microwave interference caused by multiple solid-state spin center detection modules operating simultaneously at close range, thereby improving measurement accuracy.

[0027] It is important to note that for modulated signals The fluorescence it produces can be expressed by the formula This indicates that, since demodulation is performed on AC signals and specifically on the first harmonic, the DC term V must be filtered out first during demodulation, which can be achieved, for example, through AC coupling. When performing low-pass filtering after mixing, multiple solid-state spin center detection modules can share a single filter, or filters with different cutoff frequencies can be set. The cutoff frequency is set according to the minimum frequency of the AC term to be filtered out.

[0028] The modulation signal in this embodiment can be a sine, cosine, or square wave. Since the square wave signal can be expanded into a Fourier series, its principle is the same as that of sine modulation.

[0029] like Figure 3 As shown, each solid-state spin center detection module 1 includes a quantum probe 11 containing a solid-state spin center, a microwave antenna 12, and a detection module 13; the microwave antenna 12 receives modulated microwaves transmitted from the microwave source 3 and radiates the modulated microwaves to the quantum probe 11; the quantum probe 11 is also used to sense magnetic fields and receive laser irradiation.

[0030] The detection module 13 includes a fluorescence detection module for collecting the fluorescence generated by the quantum probe 11, outputting a fluorescence electrical signal, and transmitting the fluorescence electrical signal as a detection signal to the processing module 4. The fluorescence detection module includes a filter 131, a first photodetector 132, and a first voltage conversion circuit 133. When using fiber optic laser transmission and placing the quantum probe 11 on the end face of the fiber, the fluorescence detection module is located on the side of the diamond opposite to the end face of the fiber. The fluorescence generated by the quantum probe 11 is filtered out by the filter 131, collected by the first photodetector 132, converted into an electrical signal, and then converted into a voltage signal by the first voltage conversion circuit 133 before being output to the processing module 4. The voltage conversion circuit can be a transimpedance amplifier.

[0031] Multiple solid-state spin center detection modules 1 can be used as follows Figure 1 The arrays shown are arranged at intervals on the outer circumference of the conductor 5 under test with the center of the cross section as the center. They can also be located on one side of the conductor 5 under test, or divided into two arrays located on both sides of the conductor 5 under test. When the distance between two adjacent quantum probes is no more than 10cm, microwave interference will occur. The distance between the two probes refers to the straight-line distance between the opposite surfaces of the two probes. Using the current sensor of this embodiment, even if two adjacent probes are brought close to each other with a distance of 1cm, the mutual interference of microwaves can be reduced. Figure 1 The example provides four solid-state spin center detection modules 1, but other numbers are also possible, preferably 2n, where n is an integer. The microwave antenna 12 can be a microstrip antenna, such as a coplanar waveguide antenna, and is located close to the quantum probe 11, for example, on one side of the quantum probe 11, radiating microwaves to it.

[0032] Microwave source 3 can be one or more. When set to one, it can employ multiple channels to transmit modulated microwaves to multiple solid-state spin center detection modules. After receiving the frequency modulation signal transmitted by processing module 4, microwave source 3 modulates the microwave frequency and then transmits the modulated microwave to a microwave antenna. The frequency modulation signal includes multiple different modulation frequencies, each corresponding to a different microwave antenna. During demodulation, processing module 4 uses a reference signal of the same frequency to demodulate the signal based on the modulation frequency corresponding to each antenna. In this embodiment, microwave source 3 can also have microwave amplification, isolation protection, and other microwave processing functions to meet usage requirements.

[0033] Laser source 2 is a laser, which generates excitation light to excite color centers.

[0034] For a fixed sensor system, different modulation frequencies will result in a corresponding fixed phase in the fluorescence response. This phase can be obtained experimentally under the influence of a single modulation frequency. This embodiment uses biphase demodulation technology, employing two reference signals, namely... , After mixing the two reference signals with the fluorescence signal and performing low-pass filtering, two components can be obtained. , By adjusting the phase so that one component, for example X, approaches zero, the other component Y becomes the desired value. Figure 5 The demodulation curves shown are for the case of the eight resonant frequencies of the diamond NV color center.

[0035] Processing module 4 may include, for example, the following: Figure 4 The analog-to-digital converter 41 and demodulation module 42 shown are used to acquire the detection signal transmitted by the detection module 13 and transmit it to the demodulation module 42. The demodulation module 42 calculates the current based on the demodulated data. Specifically, it first obtains the resonant frequency based on the demodulated data, then calculates the magnetic field strength value based on the resonant frequency, and finally calculates the current value based on the relationship between the magnetic field strength value and the current value.

[0036] One method to obtain the resonant frequency is to plot the demodulated data as a function of frequency by sweeping the frequency curve and finding the resonant frequency point on the curve. Another method is to use a closed-loop control algorithm to adjust the frequency of the modulated microwave radiated by the microwave source after obtaining the resonant frequency point through the first frequency sweep, in order to obtain the resonant frequency corresponding to the magnetic field. This method is called frequency tracking, which can improve efficiency. The closed-loop control algorithm used is, for example, the PID algorithm. When using the frequency sweep method, if there are errors in the demodulated data, it may lead to the absence of a zero-crossing point or an incorrect zero-crossing point in the demodulation curve, resulting in an incorrect resonant frequency. It should be noted that if multiple probes operating simultaneously have the same microwave frequency, the multiple probes will affect the fluorescence in terms of microwave power. Whether the superimposed power weakens or enhances is uncertain, which may also lead to errors in the obtained zero-crossing point. When using the PID algorithm for control, for each demodulated data, the slope of the curve segment where the zero-crossing point is located in the initial demodulation curve is usually used to calculate the microwave offset to be adjusted each time, in order to calculate the new resonant frequency. If there are errors in the demodulated data, the calculated resonant frequency will be incorrect. In this embodiment, after demodulating the correct fluorescence signal, the above-mentioned errors can be reduced.

[0037] The demodulation module can be programmed for demodulation, for example, using FPGA programming, or it can be demodulated and transmitted to the microwave source via a quadrature digital lock-in amplifier. When there are multiple detection modules 13, the analog-to-digital converter 41 can be multiple corresponding to each detection module 13, or it can be a single multi-channel converter.

[0038] Solid-state spin color centers can be one of the following: diamond nitrogen-vacancy color centers, diamond germanium-vacancy color centers, diamond silicon-vacancy color centers, silicon carbide silicon-carbon double-vacancy color centers, silicon carbide silicon-vacancy color centers, or hexagonal boron nitride boron-vacancy color centers. All are based on the principles of photoluminescence and fluorescence response to changes in the magnetic field. Quantum probes can be nano- or micron-sized particle structures. Taking diamond nitrogen-vacancy color centers as an example, quantum probe 11 is a blocky structure of diamond particles or rectangular bodies containing nitrogen-vacancy color centers, with a size ranging from tens to hundreds of micrometers.

[0039] The wavelength of the excitation light may differ for different solid-state spin color centers. For example, 532 nm green excitation light is generally used for diamond nitrogen-vacancy color centers and hexagonal boron nitride boron-vacancy color centers; 900-940 nm excitation light is used for silicon carbide double-vacancy color centers; and other color centers can be excited using corresponding excitation light. The placement of the quantum probe in the magnetic field can be chosen so that the direction of the magnetic field acting on the solid-state spin color center is parallel to the axis of one of the color centers. Therefore, when calculating the magnetic field component along this single axis, it is the magnetic field strength generated by the conductor under test along its circumference.

[0040] The modulation frequency difference between the microwaves supplied to each pair of adjacent solid-state spin center detection modules is no less than 1 kHz, ensuring efficient low-pass filtering during demodulation and improving the signal-to-noise ratio. Furthermore, each modulation frequency is no greater than the maximum modulation frequency acceptable to the spin center, achieving optimal center response. The maximum modulation frequency can be determined experimentally; for example, the acceptable modulation frequency for diamond NV centers is 10-100 kHz.

[0041] Example 2: Based on Example 1, this example... Figure 4 As shown, the detection module 13 is equipped with a fluorescence detection module, a laser detection module, and a differential circuit 134. The laser transmitted from the laser source 2 to each solid-state spin center detection module 1 is divided into two paths. One path is transmitted to the quantum probe 11, where the fluorescence detection module collects the fluorescence generated by the quantum probe 11 and outputs a fluorescence electrical signal. The other path is transmitted to the laser detection module and converted into a laser electrical signal. The differential circuit receives the fluorescence electrical signal and the laser electrical signal, performs differential processing on them, and transmits the resulting differential electrical signal as a detection signal to the processing module 4.

[0042] The fluorescence detection module includes a filter 131, a first photodetector 132, and a first voltage conversion circuit 133. The laser detection module includes a second photodetector 135 and a second voltage conversion circuit 136. Of the two laser beams, one is transmitted to the quantum probe 11. The fluorescence generated by the quantum probe 11 is filtered out by the filter 131 in the fluorescence detection module and collected and detected by the first photodetector 132, converting it into a fluorescence electrical signal. The other laser beam, used as a reference laser, is transmitted to the second photodetector 135 in the laser detection module and converted into a laser electrical signal. The current signals output from the two photodetectors are then converted into voltage signals by the voltage conversion circuits, and then differentially processed by the differential circuit 134. The resulting differential electrical signal is transmitted to the processing module 4. Using differential electrical signals from fluorescence and a laser of the same source reduces the influence of common-mode noise and improves the signal-to-noise ratio and accuracy of the measurement. The laser beam from the laser source 2 can be split using a beam splitter.

[0043] Example 3: This example provides a quantum current detection method to reduce microwave interference, including: placing multiple quantum probes containing solid-state spin centers in the magnetic field generated by the current to be measured, irradiating each quantum probe with laser light and radiating modulated microwaves, the modulation frequency of the microwaves transmitted to each pair of quantum probes being different, collecting the fluorescence generated by the detection quantum probes to obtain a detection signal, demodulating the detection signal to obtain demodulated data, and calculating the magnetic field strength value and / or current value based on the demodulated data.

[0044] This embodiment can be applied to situations where multiple quantum probes are placed close together. By applying microwaves with different modulation frequencies to each probe, fluorescence interference caused by microwaves from nearby probes can be reduced, thereby demodulating the correct fluorescence during the demodulation process and improving accuracy.

[0045] The method for calculating the current based on demodulated data in this embodiment can be found in the description in Embodiment 1. Furthermore, the method in this embodiment can also be implemented using the interference-reducing quantum current sensor in Embodiment 1 or 2, which will not be elaborated here. Other related devices can also be used, as long as they can implement the method in this embodiment.

[0046] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A quantum current sensor with reduced microwave interference, comprising: The sensor comprises a plurality of solid-state spin color center detection modules, a laser source, a microwave source, and a processing module. Each solid-state spin color center detection module is configured to sense a magnetic field generated after a conductor under test is connected to a current source, receive laser light transmitted from the laser source, and receive modulated microwaves transmitted from the microwave source, collect and detect fluorescence generated by the solid-state spin color center under the action of the laser light, the modulated microwaves, and the magnetic field, and output a detection signal to the processing module. The microwave source transmits microwaves to each two solid-state spin color center detection modules at different modulation frequencies. The processing module is configured to collect the detection signal, demodulate an alternating current signal in the detection signal using a reference signal having a corresponding modulation frequency, obtain demodulation data, calculate a magnetic field strength value and / or a current value based on the demodulation data, and transmit a frequency modulation signal to the microwave source.

2. The quantum current sensor of claim 1, wherein: Each solid-state spin color center detection module comprises a quantum probe containing a solid-state spin color center, a microwave antenna, and a detection module.

3. The quantum current sensor of claim 2, wherein: The distance between each two adjacent quantum probes is not greater than 10 cm.

4. The quantum current sensor of claim 1, wherein: The microwave source transmits microwaves to each two solid-state spin color center detection modules at different modulation frequencies, and each modulation frequency is not greater than the maximum modulation frequency that can be accepted by the spin color center.

5. The quantum current sensor of claim 1, wherein: The plurality of solid-state spin color center detection modules are arranged at intervals on a circumference with the center of the cross section of the conductor under test as the center, or on one side or both sides of the conductor under test.

6. The quantum current sensor of claim 1, wherein: The processing module adjusts the frequency of the modulated microwaves radiated by the microwave source based on the demodulation data and through a closed-loop control algorithm to obtain a resonance frequency corresponding to the magnetic field, and calculates the magnetic field strength value and the current value based on the resonance frequency.

7. The quantum current sensor of claim 2, wherein: The detection module comprises a fluorescence detection module configured to collect and detect fluorescence generated by the quantum probe, output a fluorescence electrical signal, and transmit the fluorescence electrical signal as the detection signal to the processing module.

8. The quantum current sensor of claim 2, wherein: The detection module comprises a fluorescence detection module, a laser detection module, and a differential circuit. The laser light transmitted from the laser source to each solid-state spin color center detection module is divided into two paths. One path is transmitted to the quantum probe, and the fluorescence detection module collects and detects fluorescence generated by the quantum probe, outputs a fluorescence electrical signal, and transmits the fluorescence electrical signal as the detection signal to the processing module. The other path is transmitted to the laser detection module and converted into a laser electrical signal. The differential circuit receives the fluorescence electrical signal and the laser electrical signal, performs differential processing, and transmits a differential electrical signal obtained by the differential processing as the detection signal to the processing module.

9. The quantum current sensor of claims 1-8, wherein: The solid-state spin color center is one of a diamond nitrogen vacancy color center, a diamond germanium vacancy color center, a diamond silicon vacancy color center, a silicon-carbon divacancy color center of silicon carbide, a silicon vacancy color center of silicon carbide, and a boron vacancy color center of hexagonal boron nitride.

10. A quantum current detection method for reducing microwave interference, characterized in that, The method comprises: placing a plurality of quantum probes containing solid-state spin color centers in a magnetic field generated by a current to be measured, irradiating each quantum probe with laser light, radiating modulated microwaves, the modulation frequencies of the microwaves supplied to each two quantum probes being different, collecting the fluorescence generated by the probe probes to obtain a detection signal, demodulating the detection signal with a reference signal having a corresponding modulation frequency for the alternating current signal in the detection signal to obtain demodulation data, and calculating a magnetic field strength value and / or a current value according to the demodulation data.

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