All-optical NOT/OR/XOR Logic Gates Based on Photonic Crystal with Low Response Time and High Contrast Ratio

Abstract

In this research, our study aims at optimizing a new design of all-optical logic gates with higher performances by simulation. This new structure is essentially based on the interference effect using a T-shaped and cross-shaped waveguide which is realized by three nano-resonators with PhCs. The physical parameters of NOT/XOR(LG1) and OR/XOR(LG2) are optimized to operate the telecommunication wavelength equal to 1550nm. For practical use, it must have a fast response time and its characteristics are improved: high transmission power, maximally contrast ratio of the two logic gates equal to 62.38 dB. In addition, this design presented an ultra-compact size of 72.7 $\mu m^{2}$ to facilitate its integration into all-optical integrated telecommunication circuits.