Role of surface damping on hybrid modes and electric field enhancement distribution of ultrathin metal-coated dielectric microspheres illuminated by non-resonant light

Abstract

Herein, we report a theoretical investigation on the characteristic parameters of hybrid plasmonic–photonic modes (or simply hybrid modes) and electric field enhancement (EFE) distribution of ultrathin Au- and Ag-coated dielectric microspheres illuminated by non-resonant light obtained with and without consideration of the size-dependent damping (SDD) or surface damping in ultrathin metal nanoshells. From the obtained scattering and absorption spectra, the role of SDD on characteristic parameters such as wavelength locations, full width at half maximum, and EFE of the hybrid modes is investigated for the first time, to our knowledge. In addition, the effect of metal shell thickness (t) on the hybrid modes is studied. The EFE distribution inside/outside the ultrathin metal-coated dielectric microspheres illuminated by non-resonant light is investigated. More importantly, the sensitivity of the EFE distribution of bare and metal-coated microspheres is explored by slightly varying the resonant and non-resonant wavelengths.