Characteristics of light emitter coupling with surface plasmons in air/metal/dielectric grating structures

摘要

The dipole radiation power and far-field emission power in the process of dipole surface plasmon (SP) coupling over the spectral range of 400-800 nm in air/Ag/dielectric grating nanostructures with two dipole positions are evaluated based on the boundary integral equation method. Three kinds of SP coupling features are differentiated, including the plane-wave-excited surface plasmon polariton (SPP), dipole-excited SPP, and localized surface plasmon (LSP). The dipole radiation and coupling system emission powers depend on the metal nanostructure, dipole position, and spectral location. Generally, when the Ag layer becomes thinner, the major SPP and LSP coupling features redshift. The emission of a coupling system is mainly on the dipole side of the air/Ag/dielectric nanostructure, even though the metal layer is thin.