Hybrid coupling mechanism in a system supporting high order diffraction, plasmonic, and cavity resonances.

The interactions between plasmonic and photonic modes of a cavity-coupled plasmonic crystal are studied in diffraction and diffractionless regimes, which lead us to the understanding of coherent interactions between electron plasma, higher order cavity, and diffraction modes. The strong interaction between plasmonic and photonic modes is shown to enhance as well as suppress surface plasmon resonance based on cavity phase relation. Numerical and analytical approaches are developed to accurately explain the physics of the interactions evident in their characteristic dispersion graphs. Further experimental measurements confirm the theoretical predictions.