Figure 4

Plasmonic cavity with a high-index (top)/low-index (bottom) dielectric nanorod covered by silver. (a) Schematic diagram of the cavity. The cavity is placed on a sapphire substrate. (b) Calculated dispersion curves of the fundamental SPP mode for the core refractive index of 3.4 (blue) and 1.5 (green), with w = 200 nm and d = 100 nm. Adapted from [9].