A Proposal for All Optical XNOR Gate Using Photonic Crystal Based Nonlinear Cavities.

All optical logic gates can play very important roles in all optical digital systems. In this paper we designed an all optical XNOR gate. The switching part of the designed XNOR consists of two nonlinear resonant cavities. The nonlinear cavities were created by adding two nonlinear defects made of doped glass. Plane wave expansion and finite difference time domain methods were used for simulating the designed structure. The final structure has two input and one output ports. The output port is ON when the input ports have similar states. For the designed structure the delay time is about 2.5 ps. [ABSTRACT FROM AUTHOR]