High-frequency Pound-Drever-Hall sensing of a short and high-finesse fiber ring resonator

A resonant micro optic gyro (RMOG) equipped with a short and high-finesse fiber ring resonator employing the high-frequency Pound-Drever-Hall (PDH) modulation is proposed and demonstrated. The modulation frequency and index of the PDH modulation are optimized to maximize the slope of demodulation curve. Based on the optimum parameters, the lock-in accuracy of the resonant frequency servo loop in the RMOG is improved to 0.178°/h, which is almost improved by two orders of magnitude compared with that obtained for the low-frequency phase modulation.