A proposal for a demultiplexer based on plasmonic metal-insulator-metal waveguide-coupled ring resonator operating in near-infrared spectrum

In this paper, a proposal is investigated and simulated for a demultiplexer based on plasmonic metal-insulator-metal (MIM) waveguide-coupled ring resonators working in the near-infrared region (λ = 1310 and λ = 1530). The proposed structure is made up of SiO2 as insulator embedded in silver as the metal layer. It is possible to realize demultiplexing function between desired wavelengths using the proposed structure with appropriate geometrical parameters for slits and ring resonators. Three-dimensional simulations, utilizing the finite-difference time domain algorithm, are used to obtain demultiplexing function with minimum ratio equals to 9.59 ([Mean|EPort B|2]/[Mean|EPort A|2] = 9.59 for source is on at λ = 1310 and [Mean|EPort A|2]/[Mean|EPort B|2] = 38.63 for source is on at λ = 1530). Furthermore, the size of the device is in the range of hundred nanometers as its major advantage to realize compact plasmonic integrated circuits.