Photonic crystal based all optical OR and XO logic gates

Photonic crystals are promising technology in future optical signal processing and optical computing. Design and simulation of novel all-optical fundamental XOR and OR logic gates based on two dimensional photonic crystals utilizing self-collimation and splitting mechanism are reported in this paper. In a photonic crystal, self collimated beams are partially transmitted and partially reflected with a phase lag at line defect in Γ-X direction. The reflected and transmitted input beams are interfered constructively or destructively to obtain the required logic outputs. The operation of the logic gates is simulated using two dimensional Finite Difference Time Domain (FDTD) method.