We demonstrate a double-layer Si3N4 multi-ring resonator system, where an S-bend waveguide is cross-coupled with a ring cavity loaded with two sub-ring resonators. The device performance is analyzed by using the transfer matrix method. The alignment-error-induced device performance variations are also discussed. The measured spectra coincide well with the simulated results. The device has high tuning flexibility and more design freedom with two sub-rings placed above the ring cavity. The spectrum profile can also be tuned by changing the cross-coupling coefficient. A heater placed above the resonator can shift the resonant wavelength effectively.

中文翻译：

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双层交叉耦合氮化硅多环谐振器系统


我们演示了双层 Si3N4 多环谐振器系统，其中 S 形弯曲波导与装有两个子环谐振器的环腔交叉耦合。采用传递矩阵法对器件性能进行分析。还讨论了对准误差引起的器件性能变化。测量的光谱与模拟结果非常吻合。该器件具有较高的调谐灵活性和更大的设计自由度，两个子环放置在环腔上方。还可以通过改变交叉耦合系数来调整频谱轮廓。放置在谐振器上方的加热器可以有效地改变谐振波长。