A novel all optical 4×2 encoder switch based on photonic crystal ring resonators

A novel approach to design an all optical 4 × 2 encoder is proposed by employing Kerr effect in 2D square lattice of silicon rods in photonic crystals. The main operation of device is based on the concept of all optical switch. Our proposed encoder consists of two nonlinear ring resonators with L-shape waveguides, characterized by the same resonant wavelength, embedded between four parallel waveguides. The operation of encoder at third optical window (λc=1.5478μmλc=1.5478μm) is verified with Finite Difference Time Domain (FDTD) and Plane Wave Expansion method (PWE) .The proposed structure is simple with clear operating principal, low power consumption, and ultra-small size (18.5 μm × 13 μm) compared with previously reported encoders, therefore facilitate its integration into all optical communication systems.