Maintenance of self-compensated state in a K-Rb-²¹Ne atomic comagnetometer via manipulation of time-varying pump light and photoelectric feedback control

We theoretically develop a method for maintaining the self-compensated state of a K-Rb21Ne comagnetometer, which is one of the core problems in optimizing the detection sensitivity of the comagnetometer to fundamental interactions and inertial rotation. The result of Rb21Ne coupling dynamics under transverse cosinusoidal magnetic field modulation can present a dispersive response with respect to the varying 21Ne nuclear magnetic field Bn, in which a monotonic interval can be used to monitor the drift of Bn. Furthermore, the result of Rb spin poparization evolution under the constraint of self-compensated-state maintenance exhibits a large enough time scale relative to Rb spin relaxation that it can be regarded as a quasi-static process, thus the adopted time-varying pump light intensity can be obtained using Rb equilibrium polarization. Accordingly, an implementation scheme is given. This method can not only compensate the drifting ", but also promote the system to return back to the original self-compensated state through manipulation of atomic polarization via time-varying pump light, which is useful in stabilizing the system performance.