No abstract

The most recently developed optical encoders are based on non-linear Kerr effect which require high input power. Here, we report 8 to 3 optical binary encoder based on linear effects which greatly reduces the input power requirement. The proposed encoder consists of three optical 4-input port OR gates and an optical buffer gate. Simulation results have proved correct operation states of the encoder and numerical analysis is done in order to additional evaluation. The maximum switching delay and total footprint of proposed structure are about 160 fs and 1418 µm2, respectively.

An all optical encoder based triangular lattice shape photonic crystal (PC) is proposed. The device is composed of two ring resonator waveguides and two OR gate with four input ports waveguides and two output ports waveguides in triangular lattice shape PC. The band diagram of base PC structure calculated by plane wave expansion (PWE) method. Also, transmission and distribution of electrical field behaviors of the proposed device are verified by two dimensional finite difference time domain (2D-FDTD) method. The proposed 4 × 2 encoder can operate at third communication window range, considering definitions of logic 0 and 1 being the normalized transmission as less than 3% and greater than 95% respectively. Despite the nonlinear encoders, in our case, due to the non-use of non-linear effects such as Kerr effect, low input power required for encoder.