Ultra-compact terahertz all-optical logic comparator on GaAs photonic crystal platform

Abstract

Photonic crystals are suitable structures for designing various types of optical logic circuits. In this paper, an all-optical comparator is designed and simulated using two-dimensional photonic crystals. A combination of linear and point defects has been used in the proposed structure. The small number of point defects and the use of simple linear defects make this comparator simple design. One of the important features of this comparator is that it uses two outputs to compare the input bits. A small structure is used for the proposed optical comparator. Also, this structure has a delay time of 0.07 ps, which is due to the very small size of the structure and the use of a small number of defects. The simulation results show that the bit rate for the proposed comparator is 3.33 Tb/s. Therefore, this structure can be suitable for use in high-speed logic circuits.