波导环形谐振腔(WRR)是集成光通信以及光学传感器领域的关键器件之一, 其谐振曲线的形貌将影响系统的性能。针对谐振腔耦合器一阶超模传输损耗差异、谐振腔外直波导端面反射, 利用多光束干涉叠加原理, 得到了波导环形谐振腔输出谱线的表达式。利用基于单边带调制的光学矢量网络分析方法, 对制备的高横纵比的氮化硅光WRR进行了谐振曲线谱的测试, 证实了耦合器模式以及直波导端面反射对谐振曲线的影响, 实际测试曲线与理论仿真结果拟合较好。

The waveguide ring resonator (WRR) is one of the key elements in the fields of integrated optical communications and optical sensors. The performance of these systems will be affected by the shape of the resonant curve. Aiming at the difference of transmission loss between the symmetric and anti-symmetric modes of the cavity coupler, and the reflection at the end face of the straight waveguide outside the resonator, the expression of the output line of the waveguide ring resonator is obtained using the principle of multi-beam interference superposition. The high aspect ratio silicon nitride WRR is tested with an optical vector network analyzer based on single-side band modulation. The results confirm the effect of the coupler mode and the reflection at waveguide end face on the resonance curve. The actual test curves can be well fitted with the theoretical simulation results.