We propose an all-optical AND gate based on a two-dimensional photonic crystal. The device is composed of a ring resonator waveguide with two input-port waveguides and one output-port waveguide in triangular-lattice photonic crystals. Transmission behaviors of the proposed device are investigated by the finite difference time domain method. The logic AND gate can operate at various wavelengths such as 1.30, 1.43, 1.45, 1.49, 1.51, and 1.55 μm, considering the definitions of logic 0 and 1 being less than 35% and more than 95%, respectively.
