TM-optical switch based on modification of photonic band gaps in photonic crystals

A study of TM-optical switch based on a square-lattice photonic crystal with a unit cell of rotated square cylinders and four horizontal thin plates through shifting the photonic band gap by modifying the thin plates to be tubes filled with air is presented. The TM-optical switch has been numerically demonstrated by plane-wave expansion and finite-difference time-domain methods. For the TM-optical switch, the extinction coefficient reaches to -19.3dB.

I. Introduction

Photonic crystals (PC) exhibit a band gap where the electromagnetic wave cannot propagate. In recent years, as a promising candidate for optical integrated circuit, PCs have been attracting a lot of attention. Based on PCs, many kinds of devices have been proposed [1], [2].