Coupled mode analysis of nonlinear defects in photonic crystals

We present a general analysis of the coupling of nonlinear photonic crystal cavities using coupled-mode theory. The nonlinear transmission properties of two coupled nonlinear cavities have been investigated. We validate the analysis by comparing the theoretical result with rigorous numerical simulations based on finite-difference time-domain techniques. A device consisting of two nonidentical photonic crystal cavities is proposed, by which we demonstrate that this theory can be employed for designing high-contrast all-optical switches or diodes. (C) 2009 American Institute of Physics. [doi: 10.1063/1.3246783]