A T-shaped high resolution plasmonic demultiplexer based on perturbations of two nanoresonators

A compact plasmonic wavelength demultiplexer with high resolution is proposed and numerically studied by using the Finite Element Method (FEM). The simulation results agree well with theoretical analysis. The demultiplexer wavelength can be easily manipulated by appropriately choose the geometric size and the refractive index of the dielectric filled in the cavities. Two wavelengths with a separation of 8 nm can be separated by the proposed demultiplexer. It is found that there is a trade-off between high resolution and high transmission power. This work may have potential applications in highly integrated photonic circuits.