Analysis on the magnetic field response for nuclear spin co-magnetometer operated in spin-exchange relaxation-free regime

A nuclear spin co-magnetometer operated in the spin-exchange relaxation-free (SERF) regime is a promising tool for long-term navigation application for its abilities to sense inertial rotation and to suppress environmental magnetic field disturbance. The magnetic field response model of a K-Rb-²¹Ne nuclear spin co-magnetometer is derived based on the state space method and the model is experimentally validated on a tabletop SERF co-magnetometer. The theoretical and experimental results indicate that the relaxation rate of the nuclear spins limits the field-suppression ability. The results here not only give insight into the nature of self-compensate characteristic but also provide a precise model for the estimation of the magnetic noise-induced rotation measurement error in a SERF co-magnetometer.