Low-cross-talk and high-contrast all optical bistable switching based on coupled defects in a nonlinear photonic crystal cross-waveguide geometry

•A photonic crystal all-optical switch configuration is proposed.•The cross-talk between the signal and control is eliminated.•A high transmission contrast is achieved.

We present a photonic crystal all-optical bistable switch configuration consisting of crossing perpendicular waveguides geometry with instantaneous Kerr nonlinearity. A microcavity is added to the signal waveguide which is coupled with the defect at the waveguide intersection to increase the transmission contrast. We demonstrate with the finite-difference time-domain method that such a configuration can function as a low crosstalk and high contrast all-optical switch.