Geometrical control of the resonances and mode composition in hybrid plasmonic photonic crystals

Hybrid optical materials combining metallic plasmonic and dielectric photonic crystals in one hetero-structure possess several resonance mechanisms which critically influence light transport. In particular, a hybrid consisting of a monolayer of dielectric spheres assembled on a metal film-coated substrate simultaneously supports dielectric and surface plasmon polaritons (SPPs), Fabry-Perot resonances of the effective dielectric slab and Mie resonances of individual spheres. A seemingly powerful method to control the optical behavior of such hybrids is to play with the package density of spheres in the monolayer. But up to now this approach achieved only incremental variations. However, in this report we demonstrate that reduction of the sphere size by preserving the lattice constant brings dramatic changes to the optical response of the structure, if a semitransparent metal substrate is used.