Miniaturized Si 3 N 4 Resonator With a High Polarization Extinction Ratio and Quality Factor for Improving the Sensitivity of Resonant Integrated Optical Gyroscope

Resonant integrated optical gyroscope (RIOG) has significant potential for miniaturization and high-resolution sensing. This work reports a 16-mm-diameter Si₃N₄ resonator that achieves simultaneous high polarization extinction ratio and quality factor (Q). Polarization selectivity is achieved by combining a bending-loss-induced cutoff with offset S-bend waveguide filters. TheQfactor is enhanced by implementing an under-coupled operation regime in an ultrathin-core waveguide architecture. And thermal stability is ensured via interfacial stress engineering, which involves cycles of re-etching and dual annealing. The aforementioned approaches achieve dual breakthroughs—a polarization extinction ratio exceeding 1800 dB/m and aQof 14 million, preservingQfrom –40 to 60 °C. These advancements collectively result in record-long bias stability of 0.19 deg∙h-1, achieving tactical-grade resolution in RIOG. The achieved performance marks a significant step toward the practical deployment of RIOGs.