A Closed-Loop Model of the Single-Beam SERF Atomic Magnetometer

The bandwidth and dynamic range of spin-exchange relaxation-free (SERF) atomic magnetometers (AMs) are effectively broadened by introducing magnetic field closed-loop control, rendering it a focal point in AM research. However, there is a deviation between the commonly used closed-loop AM model and the single-beam closed-loop AM experimentally constructed. In this study, we comprehensively analyzed each component in the actual system and proposed a closed-loop model of the single-beam SERF AM. The accuracy of the proposed model was varied through a comparative experiment with different control parameters. Based on comparative experiments, a tenfold reduction was verified in the mean square error of the proposed model compared with the commonly used closed-loop model. As an accurate model is essential for effective closed-loop control, the proposed closed-loop single-beam SERF AM model provides a theoretical foundation for the research and application of closed-loop AMs.