A Microscale Numerical Analysis of Ex-OR and Ex-NOR Logic Gates by Using Single Plasmonic MZI

Abstract

This work is focused on a detailed mathematical and numerical simulation–based analysis of Ex-OR and Ex-NOR logic gates at microscale by employing metal-insulator-metal (MIM) plasmonic waveguide–based Mach-Zehnder interferometer (MZI). The geometry of MIM waveguide is designed by considering the air as dielectric material in between silver metallic layers. The bulk plasma frequency and damping constant of silver metallic layers are considered as ωp = 140 × 1014 rad/s and $${\varvec{\gamma}}=$$ 0.4 × 1014 rad/s, respectively. A nonlinear Kerr-material with response in the order of picosecond is employed in linear arms of MZI to switch the phase of optical signals. The design of single MZI is modelled within the footprints of 19 × 3 µm with a high extinction ratio (ER) of 29 dB. The phase change property of MZI is utilized to validate the operation of Ex-OR and Ex-NOR gates. The results suggest that the proposed plasmonic-based logic gates can pave the path for efficient all optical signal processing system.