Analysis of Polarization-Maintaining Waveguide used in Resonance Integrated Optical Gyro

摘要

A polarization-maintaining (PM) waveguide used in Resonance Integrated Optical Gyro (RIOG) is theoretically proposed. Three essential factors determining the PM performance, which are the single-mode condition, birefringence and core index, are analyzed and optimized respectively. The single-mode rectangular waveguide is obtained by analyzing the propagation mode of the rectangular waveguide. A high birefringence waveguide design method is brought up according to the theory of geometrical birefringence, realized by changing the cross-sectional shape of the waveguide. The effect that the core index contributes to the birefringence is also discussed, and an optimal core index of the waveguide to reach maximal birefringence is determined in the condition of single-mode transmission. The high birefringence PM Waveguide with geometrical birefringence of 1.5×10~(-4) is obtained by theoretical analysis, the simulation results shows that the polarization cross-talk in RIOG is obviously improved.