Performance Analysis of Planar Nanocavities-Based Wavelength Demultiplexer for Optical Communication Systems

Abstract

This paper presents the design and analysis of planar plasmonic wavelength demultiplexer for optical communication systems. The demultiplexer is based on silver-air-silver plasmonic waveguide supported by two nanocavities for each drop channel. One cavity is used as a resonant tunneling-based channel drop filter while the other is used to realize wavelength-selective reflection feedback in the bus waveguide.  For each channel, a parametric study is performed to characterize the performance of the two corresponding nanocavities when they are operating in isolated mode.  The results are then used as a basis to design a single-channel demultiplexer by introducing the coupling between the two nanocavities. Simulation results are reported for a three-channel demultiplexer (1550, 1300, and 850 nm) using Computer Simulation Technology (CST) software package. A drop efficiency as high as  is obtained for each drop channel in the designed demultiplexer. The simulated results can be used as a guideline to design ultra-compact wavelength-division multiplexing (WDM) systems in highly integrated optical circuits.