Single-channel vector magnetic information detection method based on diamond NV color center*

A method of detecting the single channel triaxial magnetic field information based on diamond nitrogen-vacancy (NV) color center is introduced. Firstly, the incident angle of the bias magnetic field which can achieve the equal frequency difference optically-detected magnetic resonance (ODMR) spectrum of diamond NV color center is calculated theoretically, and the triaxial magnetic information solution model is also constructed. Secondly, the microwave time-controlled circuit module is designed to generate equal timing and equal frequency difference microwave pulse signals in one channel. Combining with the optical detection magnetic resonance technology, the purpose of sequentially locking and detecting the four formant signals on one side of the diamond NV color center (m s = –1 state signal) is achieved, and the vector magnetic field information detection is accomplished by combining the triaxial magnetic information solution model. The system can obtain magnetic field detection in a range of 0 mT–0.82 mT. The system’s magnetic noise sensitivity is 14.2 nT/Hz1/2, and the deviation angle errors of magnetic field detection θx and θy are 1.3° and 8.2° respectively.