Plasmonic nanoslit-based dual-wavelength multiplexer

摘要： A novel plasmonic dual-wavelength multiplexer to couple free-space waves to metal–insulator–metal (MIM) waveguides is proposed, designed and simulated. The proposed structure is based on two nanoslits carved on a metal film. Through an appropriate spacing between the nanoslits, it is possible to design this structure to couple two different wavelengths onto MIM modes such that they propagate in the same direction. The designed structure is simulated using FEM technique, and results for circular and plane wave fronts are demonstrated. High extinction ratio of greater than 10 dB is obtained in all the cases.