Surface plasmon routing in dielectric-loaded surface plasmon polariton waveguides

摘要

Waveguiding by dielectric-loaded surface plasmon-polaritons (DLSPP) structures are numerically and experimentally investigated. We used the effective index model to understand the influence of basic waveguide parameters such as width and thickness on the properties of the surface plasmon guided modes. A waveguide was fabricated and experimentally studied. The effective indices of the modes supported by the waveguide and their propagation length are evaluated by leakage radiation microscopy in both the Fourier and imaging planes. Several excitation schemes were tested including surface plasmon coupling by diascopic or episcopic illumination as well as defectmediated excitation of guided modes. We found good agreement between theoretical values predicted by the effective index model and experimental values deduced from leakage radiation images.