Design of optical logic gates based on line defect and phase difference between incident beams in two dimensional photonic crystal

a novel device based on two dimensional square lattice photonic crystals and creation phase difference between beams by defects is proposed and investigated. The device hastwo input ports and two output ports and its operation is similar to XOR and OR logic gates. The photonic crystalstructure is composed of cylindrical silicon rods in the air andline defects in the X and Z direction waveguide. Utilizing the plan wave expansion (PWE), and finite-difference time-domain (FDTD) methods, photonic band gap (PBG) and electrical field distribution is calculated respectively. It has been shown that when the phase difference between beams equal to /2, the two input beams have interfere constructively or destructively torealize the logical functions. According to this we design the XOR and OR logic gates and show the results

Keywords:

component , Photonic crystal waveguide , localized mode , phase differenc , logic gates