提出一种可同时支持横电模和横磁模传输的微环光开关设计方法, 可用于构建波长平面内的偏振无关交换芯片.为了实现微环光开关的偏振无关传输, 横电模和横磁模应工作在同一谐振波长且在该波长处有相同的群折射率, 据此采用MODE Solutions优化基于硅绝缘体波导结构的微环参数, 建立Interconnect芯片仿真模型, 考察微环光开关芯片的透射特性和传输特性.经过优化设计, 微环光开关的偏振相关损耗低至0.13 dB, 光脉冲传输时延为42.5 ps.研究表明, 当微环长度偏离优化值约5 nm时, 偏振相关损耗就会增加到1 dB, 其中热光效应可以用来弥补工艺偏差, 温度每变化1 K, 则可弥补2.2 nm的环长偏差.

A design method of micro-ring resonator based optical switches capable of simultaneously providing the transmission of transverse electric and transverse magnetic modes was presented, which can be applied to the buildup of polarization-independent switch chips operating in a given wavelength plane. In order to realize polarization-independent transmission, transverse electric mode and transverse magnetic mode should both work at the same resonant peak and the group refractive index of these two modes are equal to each other in this resonant wavelength. The silicon-on-insulator based micro-ring parameters were optimized with MODE Solutions, the chip simulation model was then set up by Interconnect to investigate transmission and transfer characteristics of the optical switch chip. By optimum design, the resulting micro-ring resonator based optical switching chip had a very low polarization dependent loss of 0.13 dB, while the transmission delay was 42.5 ps. Simulation shows that the length variation of the micro-ring resonator should be smaller than about 10nm for the polarization dependent loss of 1 dB, in which the thermo-optic effect can be used to compensate for the fabrication error with the perimeter change of 2.2 nm/K.