Magnetic Sensing with Nitrogen-Vacancy Centers Based on Lock-in Detection

Nitrogen-vacancy (NV) centers in diamond allow measurement of magnetic fields at nanoscale. The working principle is based on the measurement of a NV center resonance frequency shift, detected by monitoring the center's photoluminescence. Here we present a technique based on lock-in detection and simultaneous excitation of the three peaks corresponding to hyperfine interaction between the NV center and the
¹⁴
N nucleus.