Suppression of ambient temperature-caused drift in a laser power stabilization system with a liquid crystal variable retarder in atomic gyroscopes

Laser power stabilization systems with liquid crystal variable retarders have been employed in miniaturized atomic gyroscopes for the merits of low power consumption and easy integration. However, the long-term power drift of the system output with ambient temperature significantly decreases the long-term performance of atomic gyroscopes. Here, we demonstrated a method of dynamic closed-loop control based on the combination of optical power drift and ambient temperature modeling. For a continuous 45 min operation within an ambient temperature variation range of 23.7-25.3 °C, the relative Allan deviation of the output optical power was decreased by one order of magnitude from 2.29 × 10-4 to 3.35 × 10-5 after 100 s averaging time. The long-term stability of the system was significantly improved. In addition, the scheme requires no additional thermal control device, preventing the introduction of extra electromagnetic interference, which is desirable in a miniaturized atomic gyroscope.