Archimedes 32,4,3,4结构光子晶体中与偏振无关的自准直分束器

通过等频图分析并结合时域有限差分法法模拟, 在Archimedes 3²,4,3,4结构排列的二维光子晶体中同一频率下同时实现了电磁波两种偏振态的自准直. 研究发现,在该结构光子晶体中引入缺陷,当线缺陷宽度改变时, TE和TM两种偏振态光束的分束效果将会随之变化.由此通过控制缺陷宽度,分别实现了两种偏振态光束的50% ∶50%分束以及90°大角度光折弯,分束和折弯的效率都较为理想,为未来设计基于光子晶体的新型光子学器件提供了一种新的思路.

Polarization-independent self-collimation bends and beam splitters in 32,4,3,4 Archimedean photonic crystals

By using equi-frequency contour analysis and finite-difference time-domain simulation, self-collimation for TE- and TM-polarizations are achieved at the same frequency in two dimensional 3²,4,3,4 Archimedean photonic crystals. The bends and beam splitters are realized by truncating an air block in the photonic crystals. It is observed that the line defect can produce a tunable one-to-two beam splitter by controlling the width of the air block. A bend and a 1 ∶1 beam splitter for the TE- and TM- polarization are designed respectively, both have high efficiency. This study proposes a new design method for optical devices based on photonic crystals.