An ultra fast optical reversible gate based on electromagnetic scattering in nonlinear photonic crystal resonant cavities

Optical reversible gates are required in realizing all optical digital data processing. In reversible gates, there is a one by one mapping between the input and output ports which helps us to recover the inputs from the outputs. In this paper we aim to design and propose all optical reversible XOR and XNOR gates based on electromagnetic scattering phenomenon in nonlinear photonic crystal structures. For realizing the proposed structures a special resonator was proposed which consists of two cross connected waveguides along with some linear and nonlinear defect rods. The proposed structure will be simulated using finite difference time domain method. The simulation results show that the maximum time delay for the proposed structures is about 10 ps. The truth tables for the both structures prove that there is one by one mapping between the inputs and outputs of the proposed structures.