All-optical Fredkin gate using photonic-crystal-based nonlinear cavities

An all-optical Fredkin gate was proposed and designed. The Fredkin gate is a reversible logic gate. For designing the proposed structure we used three different optical nonlinear resonators. The wide-bandwidth resonators do not have switching functionality. However, the proposed resonator was modified to act as an optical switch in the horizontal direction. The final structure was designed using four wide-band resonators, twelve sharp resonators, and four nonlinear ring resonators. Simulation results show that the maximum rise time for the proposed structure is about 5 ps.