Design and simulation of normally open and normally closed all-optical switches based on photonic crystal triple-waveguide directional coupler

Abstract

In this paper a novel photonic crystal all-optical switch is proposed. The proposed switch which can be made from Gallium arsenide, is based on a triple-waveguide directional coupler that exhibits Kerr effect nonlinearity. Two types of switches: normally open and normally closed, are derived from the proposed topology. One of the advantages of the suggested switch is the minimum input signal reflection. The chip area for the implementation of the switch is reduced in comparison with pervious works. All dimensions have been optimized for the fiber optic communications in the wavelength of 1550 nm. The employed simulation methods are Plane Wave Expansion, Finite Difference Time Domain and Coupled Mode Theory.