Compact silicon hybrid plasmonic microring resonator-based polarization demultiplexer

Abstract

A compact silicon-based polarization demultiplexer (P-DEMUX) composed of a microring resonator in hybrid plasmonic waveguides and two bus channels in silicon wires is proposed and characterized. The modal analysis shows that the behaviors of TE modes for the hybrid plasmonic microring and silicon wire are similar, while those of TM modes illustrate significant difference, leading to strong polarization-dependence. As a result, the input TE mode can output from the drop port at the resonant wavelength while the input TM mode directly outputs from the through port with nearly neglected coupling. The present P-DEMUX can be easily applied to construct on-chip wavelength/polarization division multiplexing, further increasing the capacity of the interconnect system. Results show that a compact P-DEMUX is achieved, where the radius of the microring in the center is only 2.042 µm, and the extinction ratio and insertion loss are, respectively, ∼18.04 (19.89) and ∼0.61 (0.42) dB for TE (TM) mode, at the wavelength of 1550 nm. In addition, fabrication tolerances to the structural parameters are analyzed in detail and the evolution of the input field through the proposed P-DEMUX is also presented.