Compact 4-bit all optical digital to analog converter based on photonic crystal ring resonators

Abstract

A compact all optical 4-bit digital-to-analog converter (DAC) based on 2D photonic crystals is proposed to operate in the III transmission window 1550 nm of optical communication systems. The DAC consists of a photonic crystal ring resonator whose operation is based on the nonlinear Kerr effect. The overall operation of the proposed DAC is analyzed using the finite difference time domain method and plane wave expansion method. The total footprint of the proposed structure is 1150 µm2 with silicon rods of refractive index equal to 3.4641 placed in an air substrate with a 2D square lattice, exhibiting an insertion loss of −11 dB and absolute error of 2.79% which is suitable for photonic integrated circuits.

Photonic-crystal-based design and FDTD simulation of all-optical NAND and NOR gates with improved contrast ratio

“…The micro ring resonators have excellent features, such that the original power can build up in the micro ring and keep circulating inside the ring cavity [26]. The nonlinear Kerr effect was effectively used to design various important optical devices like ring-resonatorbased optical logic gates [27,28], digital to analog converters and 2-to-4 decoders [29][30][31]. An all-optical half adder [32] and a Toffoli gate [33] were studied using the interference effect.…”