In Situ Measurement of High-Frequency Magnetic Field Produced by Electric Heaters in Atomic Sensors

In this study, an in situ measurement method for the high-frequency magnetic field (HFMF) produced by electric heaters in atomic sensors has been proposed for the first time. It is hypothesized and demonstrated that the HFMF generated by electric heaters can be equated to a modulation field that excites atomic spin coherence, from theory and experiment, respectively. Specifically, the spin polarization of atoms in response to the HFMF generated by electric heaters is modeled skillfully using a rotating frame based on the establishment of an optically detected magnetic resonance (ODMR) atomic magnetometer. By combining different equations of spin polarization through systematically varying the parameters of bias and modulation fields, the triaxial amplitudes of the HFMF can be rapidly obtained which are (42.26~\pm ~0.12) nT, (79.28~\pm ~0.04) nT, and (184.98~\pm ~1.98) nT, respectively. The corresponding coefficients of variation are 0.28%, 0.05%, and 1.07%, respectively. The agreement observed between experimental and simulation results provides robust confirmation of the reliability and utility of the method put forth in this study. Our method presented here implements the in situ measurement of HFMF generated by electric heaters, avoiding positional errors arising from non-in situ measurement methods, which has the potential for miniaturized and low-cost atomic sensor applications.