Integrated NV (Nitrogen Vacancy) Vector Magnetometer in Real-Time Utilizing Frequency-Hopping Method

Nitrogen vacancy (NV) centers in diamond exhibit the advantages of high resolution, high sensitivity, and error-free sensing in the field of vector field detection, which bolsters the potential of NV center magnetometers for practical applications. However, most of the NV center magnetometers are still limited by the constraints imposed by bulky laboratory instruments, and the method of sweeping frequency points to detect resonance frequencies can also lead to slower detection of vector magnetic fields (MF). To address these limitations and enhance the portability of integrated vector magnetometers, we made an integrated vector magnetometer based on NV centers and proposed a microwave (MW) frequency-hopping method to realize vector MF triaxial real-time (400 ms) detection. The experimental results indicate that the magnetometer dynamic range is
$\pm 130 ~\mu \text{T}$
along the x-axis,
$\pm 110 ~\mu \text{T}$
along the y-axis, and
$\pm 260 ~\mu \text{T}$
along the z-axis, with the minimum standard deviation of vector MF measurements across all three axes being 1.84 nT. The frequency-hopping method is more than 87 times faster than the sweeping method and the size of the integrated NV magnetometer fits in the palm of the hand for portable usage. This proposal, which accomplishes vector MF rapidly measure using a self-made NV centers magnetometer, has potential applications in fields such as medical diagnosis, new energy battery testing, and geomagnetic detection.