Quantum magnetometer device based on diamond nitrogen-vacancy color center

Abstract

The invention discloses a quantum magnetometer device based on a diamond nitrogen-vacancy color center. The quantum magnetometer device comprises a laser emission unit used for generating a 532nm laser beam based on a laser trigger signal; the beam shaping unit is used for focusing the laser beam to the diamond sample; the diamond sample comprises an NV color center array with specific depth on the surface or in the diamond sample, and electrons in NV color centers are excited based on laser beams to transition and generate fluorescence; the fluorescence collection unit is used for separating exciting light from 650-800nm fluorescence signals and converting the fluorescence signals into multi-channel electric signals; the microwave radiation unit is distributed around a diamond sample space and emits three independently regulated microwave frequencies at the same time; and the control and processing unit is used for receiving and processing the multi-channel electric signals in real time and analyzing magnetic field parameters based on the optical detection magnetic resonance spectral line. Synchronous measurement of a three-dimensional magnetic field is realized, and the limitation of single-axis measurement of a traditional NV magnetometer is broken through.

Description

Technical Field

[0001] The present invention relates to the field of quantum sensing and measurement technology, and more particularly to a quantum magnetometer device based on diamond nitrogen-vacancy color centers. Background Art

[0002] With the rapid development of quantum sensing technology, magnetometers based on nitrogen vacancy (NV) color centers have shown broad application prospects in fields such as bioimaging, materials science, and basic physics research due to their ultrahigh sensitivity and nanoscale spatial resolution. However, traditional NV color center magnetometers still face many technical challenges in practical applications. For example, the system is large and difficult to meet the requirements of portability and integration. At the same time, its measurement method is usually limited to a single axis direction and cannot achieve synchronous detection of three-dimensional magnetic fields, which limits its application in complex magnetic field environments.

[0003] To address these issues, existing technologies attempt to achieve compact system designs by integrating micro-lasers with microwave sources. While this has facilitated miniaturization to some extent, it has not fundamentally overcome the limitations of single-axis measurement and cannot achieve real-time, simultaneous detection of three-dimensional magnetic fields. Additionally, some studies have proposed using Hall effect probes to assist in locating the NV axis, thereby expanding its vector magnetic sensing capabilities. However, this approach often results in complex system structures and cumbersome operations, hindering practical application and engineering applications.

[0004] Therefore, a new technical solution is urgently needed to achieve efficient and synchronous measurement of three-dimensional magnetic fields while ensuring high sensitivity, while also balancing system integration and practicality. This invention, proposed in this context, effectively overcomes the shortcomings of existing technologies by introducing multi-antenna cooperative radiation and adaptive optics to construct a highly sensitive three-dimensional magnetic field measurement platform. Summary of the Invention

[0005] In view of this, the present invention provides a quantum magnetometer device based on diamond nitrogen-vacancy color centers, and proposes a quantum magnetometer device based on NV color centers with a reasonable structure and superior performance. It can effectively solve the problems of large volume, limited dimension, and complex system in current magnetic field measurement, and has good prospects for promotion and application.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] A quantum magnetometer device based on diamond nitrogen-vacancy color centers, comprising:

[0008] Laser emission unit: used to generate 532nm laser beam based on laser trigger signal;

[0009] Beam shaping unit: used to focus the laser beam onto the diamond sample;

[0010] Diamond samples contain an array of NV color centers on the surface or at a specific depth inside the diamond. Laser beams stimulate electron transitions in the NV color centers and produce fluorescence.

[0011] Fluorescence collection unit: used to separate the excitation light and the 650-800nm ​​fluorescence signal, and convert the fluorescence signal into a multi-channel electrical signal;

[0012] And microwave control and data processing subsystem:

[0013] Microwave radiation unit: spatially distributed around the diamond sample, emitting three independently controlled microwave frequencies simultaneously;

[0014] Control and processing unit: used to receive and process multi-channel electrical signals in real time, and analyze magnetic field parameters based on optical detection magnetic resonance spectrum lines.

[0015] Preferably, the beam shaping unit includes a beam expander, a focus-adjustable lens group, and a motorized translation stage;

[0016] Beam expander: used to adjust the laser beam waist diameter;

[0017] Adjustable lens group: used to adjust the focus of the laser beam in the X and Y directions;

[0018] Motorized translation stage: used to dynamically adjust the focus plane position to compensate for uneven diamond surface or changes in NV color center depth.

[0019] Preferably, the focus-adjustable lens assembly comprises:

[0020] The first cylindrical lens is used to focus the laser beam in the X direction;

[0021] The second cylindrical lens is used to focus the laser beam in the Y direction.

[0022] Preferably, the fluorescence collection unit comprises:

[0023] First achromatic lens: used to collect the isotropic fluorescence emitted by the NV color center;

[0024] Dichroic mirror: used to reflect excitation light and transmit fluorescence;

[0025] Second achromatic lens: used to image the fluorescence onto the photodetector plane;

[0026] Rotatable filter wheel: used to load filters of different bands and quickly switch bands according to measurement requirements;

[0027] Photodetector array: used to convert filtered fluorescence signals into multi-channel electrical signals.

[0028] Preferably, the microwave radiation unit comprises:

[0029] Multi-channel DDS microwave generator: used to generate three microwave signals of different frequencies based on the microwave frequency configuration signal;

[0030] Power divider: divides the microwave signal equally into three antenna channels;

[0031] Phase adjuster: independently adjusts the phase difference of microwave signals of each antenna channel to achieve three-dimensional magnetic field synthesis;

[0032] Directional coupler: used to monitor and adjust the direction and intensity distribution of microwave signals in each antenna channel;

[0033] The first microwave antenna is located above the diamond, with the radiation direction perpendicular to the diamond surface, and is used to excite the spin state sensitive to the magnetic field in the Z direction;

[0034] The second microwave antenna is located on the side of the diamond, with the radiation direction parallel to the diamond surface, and is used to excite the X-direction magnetic field component;

[0035] The third microwave antenna is arranged at a 45° angle to the first and second microwave antennas, radiating obliquely to the XZ plane to provide cross-magnetic field components and assist in three-dimensional vector calculation.

[0036] Preferably, the control and processing unit includes:

[0037] Embedded controller: used to generate synchronous control signals and send them to the laser emitting unit, microwave radiation unit and beam shaping unit respectively;

[0038] Signal processing unit: receives and processes multi-channel electrical signals in real time;

[0039] Magnetic field calculation unit: Analyzes magnetic field parameters based on optical detection magnetic resonance spectral lines.

[0040] Preferably, the specific processing process of the signal processing unit is:

[0041] After being amplified by the preamplifier, the electrical signal is sent to a 24-bit ADC converter to convert the analog signal into a digital signal;

[0042] Orthogonal demodulation technology is used to demodulate the digital signal, and the demodulated time domain signal is converted into a frequency domain signal through fast Fourier transform;

[0043] Perform peak search in the frequency domain signal, record the resonance signal intensity at each microwave frequency, and output the resonance signal intensity list corresponding to the three directional antennas as the basic data for Lorentz curve fitting;

[0044] The resonant frequencies are calculated based on Lorentz curve fitting, including two transition frequencies under X-direction antenna excitation, two transition frequencies under Y-direction antenna excitation, and two transition frequencies under Z-direction antenna excitation.

[0045] Preferably, the specific processing process of the magnetic field calculation unit is:

[0046] Calculate the magnetic field components corresponding to each direction based on the two transition frequencies under the excitation of the antenna in the X direction, the two transition frequencies under the excitation of the antenna in the Y direction, and the two transition frequencies under the excitation of the antenna in the Z direction;

[0047] Calculate the three-dimensional magnetic field vector based on the corresponding magnetic field component in each direction;

[0048] Calculates magnetic field strength and direction angle based on the three-dimensional magnetic field vector.

[0049] Preferably, the timing relationship between the laser emitting unit and the microwave radiating unit is:

[0050] The laser pulse width emitted by the laser emitting unit is adjustable from 1 to 500ns;

[0051] The microwave frequency configuration signal starts 10ns after the laser pulse width ends;

[0052] Fluorescence acquisition is started synchronously with the microwave frequency configuration signal.

[0053] Preferably, the multi-channel comprises:

[0054] First detection channel: central wavelength 685±5nm, bandwidth 10nm;

[0055] Second detection channel: central wavelength 720±5nm, bandwidth 10nm;

[0056] The third detection channel: central wavelength 780±5nm, bandwidth 10nm.

[0057] It can be seen from the above technical solution that compared with the existing technology, the present invention discloses a quantum magnetometer device based on diamond nitrogen-vacancy color centers, which realizes the synchronous measurement of three-dimensional magnetic fields and breaks through the single-axis measurement limitation of traditional NV magnetometers; at the same time, it adopts multi-antenna collaborative radiation and adaptive optical systems to improve system integration and measurement accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0058] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are merely embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying any creative work.

[0059] Figure 1 This is a schematic structural diagram of a quantum magnetometer device based on diamond nitrogen-vacancy color centers provided by the present invention.

[0060] Figure 2 This is a schematic structural diagram of the microwave radiation unit provided by the present invention.

[0061] Figure 3 This is a schematic diagram of the structure of the filter and photodetector array provided by the present invention. DETAILED DESCRIPTION

[0062] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0063] The embodiment of the present invention discloses a quantum magnetometer device based on diamond nitrogen-vacancy color centers, such as Figure 1 Shown, including:

[0064] Laser emission unit: used to generate 532nm laser beam. 532nm laser has become the optimal excitation wavelength for diamond NV color center quantum magnetometer due to its high absorption efficiency, excellent polarization ability, mature engineering support and excellent spectral separation characteristics. 532nm photons can efficiently transfer electrons from 3 A2 excites to 3 E, then nonradiatively transitions to 1 A1, ultimately emitting 650-800 nm fluorescence;

[0065] Beam shaping unit: used to focus the laser beam onto the diamond sample;

[0066] Diamond samples contain an array of NV color centers on the surface or at a specific depth inside the diamond. Laser beams stimulate electron transitions in the NV color centers and produce fluorescence.

[0067] Fluorescence collection unit: used to separate the excitation light and the 650-800nm ​​fluorescence signal, and convert the fluorescence signal into a multi-channel electrical signal;

[0068] And microwave control and data processing subsystem:

[0069] Microwave radiation unit: spatially distributed around the diamond sample, emitting three independently controlled microwave frequencies simultaneously;

[0070] Control and processing unit: used to receive and process multi-channel electrical signals in real time, and analyze magnetic field parameters based on optical detection magnetic resonance spectrum lines.

[0071] During operation, a laser emission unit emits 532nm laser pulses, which are focused by a beam shaping unit onto an array of NV color centers on the surface or at a specific depth within the diamond sample, stimulating electron transitions and generating a 650–800nm ​​fluorescence signal. This fluorescence signal is separated by a fluorescence collection unit, received by a photodetector array, and converted into a multi-channel electrical signal. Simultaneously, three independently controlled microwave frequencies are applied to the NV color centers by microwave antennas arranged in three directions to modulate their spin states. Finally, a control and processing unit processes and analyzes the received signals in real time, extracting information such as magnetic field strength and direction.

[0072] In this embodiment, the beam shaping unit includes a beam expander, a focus-adjustable lens group, and a motorized translation stage;

[0073] Beam expander: used to adjust the laser beam waist diameter and match the aperture of subsequent optical elements. The beam diameter after expansion is ≤8mm.

[0074] Adjustable lens group: used to adjust the focus of the laser beam in the X and Y directions to ensure that the laser is evenly distributed on the two-dimensional plane;

[0075] Motorized translation stage: used to dynamically adjust the focus plane position to compensate for diamond surface unevenness or NV color center depth changes, with positioning accuracy better than ±1μm.

[0076] The focus-adjustable lens set includes:

[0077] The first cylindrical lens is used to focus the laser beam in the X direction;

[0078] The second cylindrical lens is used to focus the laser beam in the Y direction.

[0079] The apertures of the first cylindrical lens and the second cylindrical lens may be 8-10 mm.

[0080] The optical path formed by the beam shaping unit satisfies the following requirements: after the laser beam is shaped, an elliptical spot with an aspect ratio of 1:1.5 is formed on the diamond surface.

[0081] In this embodiment, the fluorescence collection unit includes:

[0082] First achromatic lens: used to collect the isotropic fluorescence emitted by the NV color center;

[0083] Dichroic mirror: used to reflect excitation light and transmit fluorescence, and its aperture can be 12-15mm; more specifically, it reflects 532nm excitation light and transmits 650-800nm ​​fluorescence;

[0084] Second achromatic lens: used to image the fluorescence onto the photodetector plane;

[0085] Rotatable filter wheel: used to load filters of different wavelengths (such as 685±5nm, 720±5nm, 780±5nm), and quickly switch wavelengths according to measurement requirements;

[0086] Photodetector array: used to convert the filtered fluorescence signal into a multi-channel electrical signal. The photodetector array can use a low-noise, high-responsivity avalanche photodiode (APD), where each channel corresponds to a filter (e.g., 685nm, 720nm, 780nm) to detect fluorescence signals of different transition paths. Specifically, Figure 3 Shown, including:

[0087] First detection channel: central wavelength 685±5nm, bandwidth 10nm;

[0088] Second detection channel: central wavelength 720±5nm, bandwidth 10nm;

[0089] The third detection channel: central wavelength 780±5nm, bandwidth 10nm

[0090] In this embodiment, if Figure 2 As shown, the microwave radiation unit includes:

[0091] Multi-channel DDS microwave generator: used to generate three microwave signals of different frequencies based on the microwave frequency configuration signal;

[0092] Power divider: divides the microwave signal equally into three antenna channels;

[0093] Phase adjuster: independently adjusts the phase difference of each antenna channel to achieve three-dimensional magnetic field synthesis;

[0094] Directional coupler: used to monitor and adjust the direction and intensity distribution of microwave signals in each antenna channel;

[0095] The first microwave antenna is located above the diamond, with the radiation direction perpendicular to the diamond surface, and is used to excite the spin state sensitive to the magnetic field in the Z direction; the corresponding subsequent transition frequency is: f z，+1 and f z，-1 ;

[0096] The second microwave antenna is located on the side of the diamond, with the radiation direction parallel to the diamond surface, and is used to excite the X-direction magnetic field component; the corresponding subsequent transition frequency is: f x，+1 and f x，-1 ;

[0097] The third microwave antenna is arranged at a 45° angle to the first and second microwave antennas, radiating obliquely to the XZ plane (the Y component is 0). The oblique field in the XZ plane can simultaneously excite the spin state components in the X and Z directions, which is used to provide cross-magnetic field components to assist in three-dimensional vector solution.

[0098] Corresponding transition frequency: Due to its special angular arrangement, it can simultaneously affect the magnetic field components in the X and Z directions, but the main purpose is to accurately calculate the magnetic field component in the Y direction by combining the signals. Therefore, by jointly processing the data under the excitation of the three antennas, using matrix decomposition or vector synthesis methods, the contribution in the Y direction can be separated from the composite signal. Finally, the transition frequency f in the Y direction can be obtained. y，+1 and f y，-1 .

[0099] Each antenna in the present invention operates in the 2.6-3.2 GHz frequency range and can simultaneously transmit three independently controlled microwave frequencies. A phase modulator independently controls the phase difference of each microwave signal, enabling three-dimensional magnetic field vector synthesis. This enables the system to precisely modulate the microwave field applied to the NV color center, effectively analyzing the magnetic field distribution in three dimensions.

[0100] In this embodiment, the control and processing unit includes:

[0101] Embedded controller: used to generate synchronous control signals and send them to the laser emitting unit, microwave radiation unit and beam shaping unit respectively; specifically, generate laser trigger signals and set the pulse width to act on the laser emitting unit; set three microwave frequencies and phases to excite NV color centers in different directions and act on the multi-channel DDS microwave generator; set the microwave phase of each antenna channel to act on the phase regulator and the control signal of the adjustable lens group and the electric translation stage; at the same time, in order to achieve high-precision magnetic field measurement for the entire system and avoid mutual interference between laser and microwave, the timing relationship between the laser emitting unit and the microwave radiation unit is as follows: the laser pulse width emitted by the laser emitting unit is adjustable from 1 to 500ns; the microwave frequency configuration signal is started 10ns after the end of the laser pulse width; the fluorescence collection is started synchronously with the microwave frequency configuration signal.

[0102] Signal processing unit: Receives and processes multi-channel electrical signals in real time. Specifically, the electrical signals are amplified by the preamplifier and then sent to the 24-bit ADC converter to convert the analog signals into digital signals.

[0103] Orthogonal demodulation technology is used to demodulate the digital signal, and the demodulated time domain signal is converted into a frequency domain signal through fast Fourier transform;

[0104] Perform peak search in the frequency domain signal, record the resonance signal intensity at each microwave frequency, and output the resonance signal intensity list corresponding to the three directional antennas as the basic data for Lorentz curve fitting;

[0105] The resonant frequencies are calculated based on Lorentz curve fitting, including two transition frequencies under X-direction antenna excitation, two transition frequencies under Y-direction antenna excitation, and two transition frequencies under Z-direction antenna excitation; specifically:

[0106] (1) Lorentz curve fitting

[0107] Fit a Lorentzian function to the resonance peaks in the frequency domain signal:

[0108]

[0109] Where f0 is the resonant center frequency, Γ is the line width, and A is the intensity amplitude.

[0110] (2) Calculation of transition frequency difference

[0111] The NV color center in diamond has an electron spin S = 1 and has three energy levels in the ground state: |0>, |+1>, and |-1>. In the absence of an external magnetic field, these two excited states (±1) are degenerate; when a magnetic field B is applied, the |+1> and |-1> energy levels split due to the Zeeman effect, forming two transition peaks. Therefore, when the NV color center is excited by laser, two transition peaks f can be identified. +1 and f -1 ;

[0112] Calculate the resonant frequency difference: Δf = f +1 -f -1 ;

[0113] Calculate the magnetic field strength: B = γ·Δf, where γ is the gyromagnetic ratio.

[0114] Based on this principle, the microwave antennas in different directions (X, Y, Z) of the present invention respectively excite the NV color center and calculate the magnetic field components in each direction by detecting the corresponding transition frequencies.

[0115] Two transition frequencies under X-direction antenna excitation:

[0116] When microwaves are applied from the X-direction antenna (the second microwave antenna), they primarily affect the spin state of the NV color center along the X-axis, causing changes in the |0>→|+1> and |0>→|-1> transition frequencies. These two frequencies can be expressed as:

[0117] f x，+1 : The frequency corresponding to the |0>→|+1> transition under the antenna excitation in the X direction.

[0118] fx，-1 : The frequency corresponding to the |0>→|-1> transition under the antenna excitation in the X direction.

[0119] These two frequencies are the resonant frequency values ​​extracted from the fluorescence signal by the signal processing unit. Based on these frequency differences, the magnetic field component in the X direction can be calculated:

[0120] B x =γ·(f x，+1 -f x，-1 )

[0121] Two transition frequencies under Y-direction antenna excitation:

[0122] Similarly, when microwaves are applied to the Y-direction antenna, they primarily affect the spin state of the NV color center along the Y-axis, causing changes in the |0>→|+1> and |0>→|-1> transition frequencies. These two frequencies can be expressed as:

[0123] f y,+1 : The frequency corresponding to the |0>→|+1> transition under the Y-direction antenna excitation.

[0124] f y，-1 : The frequency corresponding to the |0>→|-1> transition under the Y-direction antenna excitation.

[0125] Similarly, these frequencies are also the resonance frequency values ​​extracted from the fluorescence signal by the signal processing unit. Based on these frequency differences, the magnetic field component in the Y direction can be calculated:

[0126] B y =γ·(f y，+1 -f y，-1 )

[0127] Similarly, the magnetic field component in the Z direction: B z =γ·(f z，+1 -f z，-1 )

[0128] With the magnetic field components in the X, Y, and Z directions, calculate the total magnetic field strength and its direction:

[0129] Total magnetic field strength

[0130]

[0131] Calculate the magnetic field direction (polar angle θ and azimuth angle φ in spherical coordinates) based on the magnetic field intensity:

[0132] Polar angle (relative to the Z axis):

[0133]

[0134] Azimuth (angle between projection on XY plane and X axis):

[0135]

[0136] In this embodiment, the timing relationship between the laser emitting unit and the microwave radiating unit is:

[0137] Laser pulse width: 1-500ns adjustable;

[0138] Microwave modulation signal: starts 10ns after the laser pulse ends;

[0139] Fluorescence acquisition window (fluorescence intensity from the photodetector): opens synchronously with microwave modulation;

[0140] The workflow of the present invention is:

[0141] The embedded controller sends a laser trigger signal. After receiving the command, the laser reflection unit emits a 532nm laser pulse with a duration of a preset value (such as 100ns); at the same time, the laser departure time is recorded as a reference timestamp.

[0142] After being expanded by the beam expander, the laser beam enters the focusable lens group: the first cylindrical lens focuses along the X direction; the second cylindrical lens focuses along the Y direction; the motorized translation stage automatically adjusts the Z-axis position according to the surface height of the diamond sample or the depth of the NV color center;

[0143] If the system detects a decrease in fluorescence intensity (e.g. due to NV layer offset), it will provide feedback to the controller to automatically adjust the focal length of the lens group and the position of the translation stage to restore the maximum fluorescence output, thus forming a focus closed-loop control.

[0144] Within 10 nanoseconds of the laser pulse's end, the embedded controller activates the microwave generator (and simultaneously starts ADC sampling). Three independent channels transmit microwave signals of varying frequencies and phases. All antennas operate simultaneously, covering the 2.6–3.2 GHz frequency range and supporting multi-frequency parallel excitation. A fluorescence collection unit separates the 650–800 nm fluorescence and feeds it into a photodetector array. The detectors output analog electrical signals, which are amplified by a preamplifier and fed into a 24-bit ADC. After data processing and analysis, the signals are output as magnetic field strength and azimuth angle.

[0145] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. Reference can be made to the common and similar parts between the various embodiments. For the devices disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple, and the relevant parts can be referred to the method description.

[0146] The above description of the disclosed embodiments is intended to enable one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be readily apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not limited to the embodiments shown herein but is intended to conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A quantum magnetometer device based on diamond nitrogen-vacancy color centers, characterized in that: include: Laser emission unit: used to generate 532nm laser beam based on laser trigger signal; Beam shaping unit: used to focus the laser beam onto the diamond sample; Diamond samples contain an array of NV color centers on the surface or at a specific depth inside the diamond. Laser beams stimulate electron transitions in the NV color centers and produce fluorescence. Fluorescence collection unit: used to separate the excitation light and the 650-800nm ​​fluorescence signal, and convert the fluorescence signal into a multi-channel electrical signal; And microwave control and data processing subsystem: Microwave radiation unit: spatially distributed around the diamond sample, emitting three independently controlled microwave frequencies simultaneously; Control and processing unit: used to receive and process multi-channel electrical signals in real time, and analyze magnetic field parameters based on optical detection magnetic resonance spectrum lines.

2. A quantum magnetometer device based on diamond nitrogen-vacancy color centers according to claim 1, characterized in that: The beam shaping unit includes a beam expander, a focus-adjustable lens group, and a motorized translation stage; Beam expander: used to adjust the laser beam waist diameter; Adjustable lens group: used to adjust the focus of the laser beam in the X and Y directions; Motorized translation stage: used to dynamically adjust the focus plane position to compensate for uneven diamond surface or changes in NV color center depth.

3. The quantum magnetometer device based on diamond nitrogen-vacancy color centers according to claim 2, characterized in that: The focus-adjustable lens set includes: The first cylindrical lens is used to focus the laser beam in the X direction; The second cylindrical lens is used to focus the laser beam in the Y direction.

4. The quantum magnetometer device based on diamond nitrogen-vacancy color centers according to claim 1, characterized in that: The fluorescence collection unit includes: First achromatic lens: used to collect the isotropic fluorescence emitted by the NV color center; Dichroic mirror: used to reflect excitation light and transmit fluorescence; Second achromatic lens: used to image the fluorescence onto the photodetector plane; Rotatable filter wheel: used to load filters of different bands and quickly switch bands according to measurement requirements; Photodetector array: used to convert filtered fluorescence signals into multi-channel electrical signals.

5. The quantum magnetometer device based on diamond nitrogen-vacancy color centers according to claim 1, characterized in that: The microwave radiation unit includes: Multi-channel DDS microwave generator: used to generate three microwave signals of different frequencies based on the microwave frequency configuration signal; Power divider: divides the microwave signal equally into three antenna channels; Phase adjuster: independently adjusts the phase difference of microwave signals of each antenna channel to achieve three-dimensional magnetic field synthesis; Directional coupler: used to monitor and adjust the direction and intensity distribution of microwave signals in each antenna channel; The first microwave antenna is located above the diamond, with the radiation direction perpendicular to the diamond surface, and is used to excite the spin state sensitive to the magnetic field in the Z direction; The second microwave antenna is located on the side of the diamond, with the radiation direction parallel to the diamond surface, and is used to excite the X-direction magnetic field component; The third microwave antenna is arranged at a 45° angle to the first and second microwave antennas, radiating obliquely to the XZ plane to provide cross-magnetic field components and assist in three-dimensional vector calculation.

6. The quantum magnetometer device based on diamond nitrogen-vacancy color centers according to claim 1, characterized in that: The control and processing unit includes: Embedded controller: used to generate synchronous control signals and send them to the laser emitting unit, microwave radiation unit and beam shaping unit respectively; Signal processing unit: receives and processes multi-channel electrical signals in real time; Magnetic field calculation unit: Analyzes magnetic field parameters based on optical detection magnetic resonance spectral lines.

7. The quantum magnetometer device based on diamond nitrogen-vacancy color centers according to claim 6, characterized in that: The specific processing process of the signal processing unit is: After being amplified by the preamplifier, the electrical signal is sent to a 24-bit ADC converter to convert the analog signal into a digital signal; Orthogonal demodulation technology is used to demodulate the digital signal, and the demodulated time domain signal is converted into a frequency domain signal through fast Fourier transform; Perform peak search in the frequency domain signal, record the resonance signal intensity at each microwave frequency, and output the resonance signal intensity list corresponding to the three directional antennas as the basic data for Lorentz curve fitting; The resonant frequencies are calculated based on Lorentz curve fitting, including two transition frequencies under X-direction antenna excitation, two transition frequencies under Y-direction antenna excitation, and two transition frequencies under Z-direction antenna excitation.

8. The quantum magnetometer device based on diamond nitrogen-vacancy color centers according to claim 7, characterized in that: The specific processing process of the magnetic field calculation unit is as follows: Calculate the magnetic field components corresponding to each direction based on the two transition frequencies under the excitation of the antenna in the X direction, the two transition frequencies under the excitation of the antenna in the Y direction, and the two transition frequencies under the excitation of the antenna in the Z direction; Calculate the three-dimensional magnetic field vector based on the corresponding magnetic field components in each direction; Calculates magnetic field strength and direction angle based on the three-dimensional magnetic field vector.

9. The quantum magnetometer device based on diamond nitrogen-vacancy color centers according to claim 1, characterized in that: The timing relationship between the laser emission unit and the microwave radiation unit is: The laser pulse width emitted by the laser emitting unit is adjustable from 1 to 500ns; The microwave frequency configuration signal starts 10ns after the laser pulse width ends; Fluorescence acquisition is started synchronously with the microwave frequency configuration signal.

10. The quantum magnetometer device based on diamond nitrogen-vacancy color centers according to claim 3, characterized in that: Multi-channel includes: First detection channel: central wavelength 685±5nm, bandwidth 10nm; Second detection channel: central wavelength 720±5nm, bandwidth 10nm; The third detection channel: central wavelength 780±5nm, bandwidth 10nm.

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