Design of 4 × 2 optical encoder utilizing nano-structure plasmonic IMI waveguides

Surface waves with their ability to pass through nanostructures opened the way to convert the electronic circuits to optical circuits. The 4 × 2 optical encoder have been designed, analyzed, and simulated optically using plasmonic structure using the COMSOL version 5.5 software package with finite element method (FEM). 4 × 2 optical encoder using silver as metal and SiO 2 and Al 2 O 3 as a dielectric with a T threshold of 40%, and operating wavelength of 1550 nm. The results were delivered in graphs containing the Transmission values (T) versus a wavelength range between 800 nm and 2000nm, electric field distribution (EF), contrast ratio (CR), modulation depth (MD), and insertion loss (IL). The maximum T was 50%, the MD was 87.2%, and the CR 8.84 dB.