Detection of radio-frequency field with a single spin in diamond

Detection of a.c. magnetic field is consequential for many developments in physical and biological sciences, and various designs of magnetometer have been proposed recently. However, the large size of sensor and the extreme measurement conditions required strongly limit their application. It remains a challenge to reconstruct the vector of a.c. field with nanoscale spatial resolution using a single spin under ambient conditions. In this work, we choose the radio-frequency (RF) field as a typical case and realize the measurement of RF field based on a nitrogen-vacancy (NV) center in diamond. We build a solid sensor through measuring the effect of RF field on NV electron spin energy levels and the transition between them. Both of the phase and amplitude (including the transverse and longitudinal components) are measured by this new approach.