Surface plasmon mediated nonradiative energy transfer and enhanced radiative emission in stratified planar nanostructures

Abstract

Planar plasmonic nanostructures have gained considerable attention due to their crucial role in the theoretical comprehension of surface enhanced fluorescent along with their wide applications in nonradiative energy transfer (NRET), plasmonic wave guided mode, Raman scattering spectroscopy, color filters, light emitting and light harvesting devices. With the availability of large density of states at the metallic surface, the radiative and nonradiative decay channels of an electric dipole in a vicinity of metal would be dramatically modified. However, the radiative enhancement cannot be realized for any desired emissive dipole as the existing plasmonic resonance frequency is limited to the well-known plasmonic materials. Despite the fact that recent studies in metamaterial structures demonstrate a promising approach of tuning Purcell factor across the emission wavelength, the structures still suffer from an inefficient radiative emission. Moreover, in the case of nonradiative energy transfer, the conventionally sandwiched donor-metal film-acceptor configurations lack the desired efficiency and suffer poor photoemission due to the high energy loss. In this dissertation, we propose and demonstrate the nonradiative energy transfer mechanism between the donor and the acceptor through multi-layered metallic nanostructuresstratified configuration, in which an efficient energy transfer can be realized. This novel approach in NRET uniquely provides us with the ability to overcome the drawback of high energy absorption losses in a thick metal film by