Design and analysis of high performance 1xN optical wavelength demultiplexers based on MIM waveguide with polygon resonators

Abstract

Confinement of the light at the subwavelength scale makes photonic devices more efficient in applications such as optical filtering, switching, and sensing with their low dimensions. Metal-insulator- metal waveguide-based configurations present many paths for manipulating light at the wide range of the electromagnetic spectrum. For that purpose, in this study, a wavelength demultiplexer (WDM) based on a metal-insulator-metal (MIM) waveguide is numerically investigated by finite difference time domain (FDTD) method. Proposed WDMs have cascade polygon resonators. After optimizing the fundamental filter, this structure is formed as 1xN demultiplexers. The proposed demultiplexers have two- and three channels. The minimum full width at half-maximum (FWHM) value for these channels is 20.02 nm and the maximum quality factor value is 47.7 at 954.9 nm wavelength. The minimum crosstalk value is obtained as -30.37 dB for this study. The proposed 1xN demultiplexers have potential tools to design low-cost integrated optical circuits for specific wavelengths.