中文摘要：

设计了一种缺陷模迁移光子晶体微腔全光开关.两条二维三角晶格空气孔光子晶体波导由一个光子晶体微腔连接,在微腔的点缺陷中填充掺有少量偶氮聚合物的苯乙炔类液晶.通过调节控制光的偏振态,使偶氮聚合物发生顺-反异构化反应,带动液晶分子重新取向,从而改变光子晶体微腔的谐振波长,进而实现光的通过与截止.运用时域有限差分法和平面波展开法分析了二维光控液晶光子晶体微腔全光开关的光学特性.数值计算结果表明：对于1.55μm通信波段通过外界偏振光控制所填充的向列相液晶的折射率可以实现对光波的导通与截止.分析结果显示,此开关具有阈值低,消光比较大,体积小等优点.

英文摘要：

A novel photonic crystal （PC） all-optical switch based on the shift of defect mode is demonstrated. Two photonic crystal waveg- uides are connected by a photonic crystal cavity. The point defect of the photonic crystal cavity is filled with phenylacetylene liquid cyrstals intermingled with azobenzene. The output of the optical switch is controlled by adjusting the rotation angle of the liquid crystals＇ orientation vector. And the optical switch is numerically investigated by using the finite difference time domain （FDTD） method and plane wave expansion method. Numerical simulation shows that the optical switch based on the PC cavity can be changed by adjusting the applied linearly polarized light. Results show that the switch has low threshold power density, great extinction ratio, and small size.