Self-collimated Slow Light in Square Lattice Photonic Crystals

Here, a 2D hole- and rod-type square array has been investigated to achieve self-collimated slow light in thestructure composed of silicon (ε=12) and air (ε=1). The plane wave expansion and equal frequency contour analysishave shown that ng~18.5 is achievable for a rod-type structure with r=0.3a for TE polarization within incidence anglesof θin<15o. Also, all-angle polarization insensitive self-collimation with ng~3 is achieved for a hole-type structure withr=0.25a. Results achieved by PWE has been further proved by FDTD method and there is a good agreement betweentwo methods.

Keywords:

Photonic crystals , Slow light , PWE , EFC , FDTD