自由光谱范围加倍的单微环谐振滤波器

基于两点耦合和光波干涉控制相移思想提出U型波导耦合单微环的谐振滤波器结构。利用传输矩阵法推导了此结构的数学模型,采用Matlab模拟了输出端口谱线形状。当微环与U型波导的两个耦合点之间的距离为微环周长的整数倍时,此新型微环谐振滤波器比传统的双直波导耦合单微环滤波器的自由光谱范围增加1倍。针对该结构参数,同时讨论了耦合系数对输出谱线的影响,得出当耦合系数为0.018时,输出谱线具有最佳的消光比,同时保持窄的带宽和高的品质因子。

Doubled Free Spectral Range of Single Micro-Ring Resonator Filter

A U-shaped waveguide-coupled single micro-ring resonator filter structure is proposed based on two-point coupling and optical interferences controlling phase shift. The mathematical model of this structure is inferred by using the transfer matrix method, and the simulation of the spectral line shape of the output port can be obtained by Matlab. By adjusting the distance of two coupling points between U-shaped waveguide and micro-ring, in contrast to traditional two-straight waveguide-coupled single micro-ring filter, the free spectral range (FSR) of the new structure can be doubled when the distance is integer multiples of the circumference of micro-ring. Aimed at the parameters of this structure, the influence of coupling coefficient on the output line is discussed as well, and the perfect extinction ratio of the output spectrum is gained while a narrow bandwidth and a high quality factor are maintained, as the coupling coefficient is 0.018.