In Situ Calibration of Magnetic Field Coils Using Parametric Resonance in Optically-pumped Magnetometers

In this article, we propose an in situ method to calibrate the magnetic-field coil systems in optically-pumped magnetometers. The method is based on parametric resonance induced by nonresonant radio-frequency (RF) fields, and is especially suitable for microfabricated single-beam zero-field atomic magnetometers. We have experimentally and theoretically demonstrated this method with a single-beam spin-exchange-relaxation-free (SERF) magnetometer, and the experiment results are in line with theoretical expectations.