一种热光可调谐级联微环滤波器的理论分析

根据Vernier效应可大幅度提高滤波器自由光谱范围和调谐范围,设计了一种热光可调谐级联微环滤波器. 利用传输矩阵方法和有限元方法从理论上计算了对于第一级微环半径为48 μm,第二级半径为50 μm的级联微环滤波器的自由光谱范围和调谐范围可以达到75.6 nm,而功耗仅为103.1 mW,这是目前为止我们 所知的基于微环谐振腔的硅基热光可调谐滤波器中最大的自由光谱范围和在如此低功耗下最大的调谐范围. 利用有限元方法,还计算了半径为50 μm微环的热光调谐响应时间,上升沿时间为3.5 μs,下降沿时间仅为0.8 μs.

Theoretical analysis of a thermal-optical tunable filter based on Vernier effect of cascade microring resonators

A thermal-optical tunable filter based on the Venier effect of cascade microring resonator, which can expand the Free-Spectrum-Range (FSR) and the tuning range, is designed and simulated. The FSR of the filter with a radius of 48 μm for the first order and 50 μm for the second order microring can be expanded to 76.5 nm, which is at present the largest FSR to our best knowledge. A tuning range covering all of the above mentioned FSR can be reached under 103.1 mW heating power, which is also the largest one for silicon based thermal-optic tunable microring resonator filers. The response time, calculated by finite-element-method, of the designed tunable filter with 50 μm radius ring is 3.5 μs for the rise edge and 0.8 μs for the fall edge.