Abstract

We investigate the effects of spatial confinement of plasmon gap-modes on pho-toluminescence in plasmonic nanostructures. The nanostructure design used is the common “particle-on-mirror” geometry using Au gratings separated from Au films by nanometric SiO₂ layers which allows for very precise and tunable gap-mode plasmon resonance. Here we present results obtained with precisely nanofabricated structures rather than rough metal films with randomly oriented plasmon “hot spots”, and show the photoluminescence spectra has a nonlinear power law dependence of p(ω) = 1 for continuous wave laser excitation and p(ω) ∝ ω for pulsed laser excitation.

© 2018 The Author(s)