Design and modelling of all-optical NAND gate using metal-insulator-metal (MIM) waveguides-based Mach-Zehnder interferometers for high-speed information processing

All the basic logic gates play a major role in carrying out the mathematical computation. The drawbacks of conventional electronics are alleviated by all-optical integrated circuits with a great application of high-speed computing and information processing. In this paper, plasmonic metal-insulator-metal (MIM) waveguides have an excellent property of propagating the surface plasmons beyond the diffraction limit up to deep sub-wavelength scale. All-optical NAND gate design is optimized by using MIM plasmonic waveguide-based Mach-Zehnder interferometers (MZIs) in the footprint of 36 mu m x 8 mu m that works at 1.55 mu m operating wavelength. The better performance of the proposed device is achieved, such as the extinction ratio is 10.55 dB, insertion loss is obtained as 0.506 dB, and response time is 262 ps. The proposed design is verified by using the finite-difference time-domain (FDTD) technique and further analysis are carried out by mathematical computation and MATLAB simulation results.