Single-beam comagnetometer using elliptically polarized light for dual-axis rotation measurement

Abstract

We have developed a single-beam spin-exchange relaxation-free comagnetometer using elliptically polarized light for dual-axis rotation measurement. The light beam propagating through the glass cell is simultaneously used for optical pumping and signal extraction. Combined with transverse magnetic field modulation, the rotation information can be collected through a balanced polarimeter module and a lock-in amplifier. Also, we propose a decoupling method by adjusting the phase shift of the reference signal, allowing the device to realize biaxial signal decoupling while still maintaining its self-compensation state. Compared to those without decoupling, our method improves the performance of our device in its signal-to-noise ratio and rotation sensitivity. The single-beam comagnetometer scheme and the decoupling method have a positive impact on the development of miniaturized atomic sensors for high-precision inertial measurement.