Plasmonic Coupler and Multiplexer/Demultiplexer Based on Nano-Groove-Arrays

Abstract

A novel plasmonic unidirectional coupler and its extension to a multiplexer/demultiplexer are proposed and simulated. The proposed structure can be etched adjacent to metal-insulator-metal (MIM) waveguides which can result in considerable reduction in footprint of optical signal processing systems. Simulated results show very good agreement with design. Extinction ratio (ER) of more than 11 dB was achieved for both the coupler as well as the multiplexer/demultiplexer. Crosstalk as well as full width at half maximum (FWHM) was also highly acceptable for the multiplexer/demultiplexer. The proposed structures have an additional attractive feature of being amenable to integration with other relevant functionalities as demonstrated in the results.