Aryan Salmanpour - Nanoptronics Research Center, Electrical and Electronics Engineering Department, Iran University of Science and Technology (IUST), Tehran, Iran
Shahram Mohammadnejad - Nanoptronics Research Center, Electrical and Electronics Engineering Department, Iran University of Science and Technology (IUST), Tehran, Iran
Pedram Taghinejad Omran - Nanoptronics Research Center, Electrical and Electronics Engineering Department, Iran University of Science and Technology (IUST), Tehran, Iran

In this paper, a photonic crystal structure including two directional couplers and one T-branch combiner is proposed in order to implement all-optical XOR logic gate. The linear directional couplers are designed based on coupled mode theory. Also, T-branch combiner is optimized with changing the radius of rods near the crosspoint of waveguides in order to enhance the performance of structure. Finite difference time domain method has been utilized to simulate the performance of proposed logic gate. Simulation results show that the ON-OFF logic level extinction ratio and bit rate of structure are about -37.56 dB and 1.63 Tbit/s, respectively.

All-optical logic gate, photonic crystal, directional coupler, extinction ratio