Heating temperature control and driving voltage nonlinear feedback of LCVR for stabilizing laser power in atomic spin gyroscopes

Atomic Spin Gyroscopes (ASGs), used in high-precision applications such as navigation and geophysical sensing, require stable laser power for accurate readings. Fluctuations in pump laser power directly impact the spin polarization of alkali atoms, compromising the gyroscope’s stability. Stabilizing laser power with Liquid Crystal Variable Retarder (LCVR) offers advantages over other methods, including compact size and reliability. However, its performance is constrained by temperature sensitivity, slow response times, and nonlinear dynamics, limiting the potential for further improvement in ASGs performance. This paper proposes a solution that integrates heating temperature control with driving voltage nonlinear feedback to address these challenges. First, heating control is applied to the LCVR. Then, based on the developed physical model that captures the nonlinear dynamics of the LCVR, a nonlinear controller is designed to stabilize the laser power. Experimental results demonstrate that, under heating control, the LCVR’s step response reduces settling time by 47.7%. Furthermore, the proposed approach increases control performance by 186.8% and improves electron spin polarization stability, with Allan deviation reduced by up to 69.7%. The proposed method provides technical support for enhancing the performance of ASGs.