Strongly enhanced ultraviolet emission of an Au@SiO₂/ZnO plasmonic hybrid nanostructure

Abstract

We present the surface plasmon polariton (SPP)-enhanced ultraviolet (UV) emission of an Au@SiO2/ZnO hybrid nanostructure. We achieved approximately 20- and 8-fold enhancements of the UV-emitting intensities from Au-SPP coupled nanometre- and micrometre-scaled ZnO wires through an optimized 5 nm-thick SiO2 spacer compared to that obtained from bare ZnO on a Si substrate without SPP coupling. Cathodoluminescence measurements and simulations demonstrated that the plasmonic hybrid nanostructure enables the strong localization of the SPP field, resulting in significantly enhanced UV emission. This plasmonic structure paves the way to nanoscale UV-optical lasers and sensors.