Plasmonic Enhancement of Single Photon Emission from a Site-Controlled Quantum Dot

Abstract

We showed enhanced single photon emission via exciton–plasmon coupling in a metal-encapsulated site-controlled quantum dot (QD) structure. It was observed that the average QD luminescence was enhanced by a factor of 7.33 ± 1.32 and the exciton lifetime was reduced by a factor of 12.8 ± 1.10. The exciton–plasmon coupling was enhanced by matching the exciton energy to the localized surface plasmon resonance. Due to the sensitivity of the plasmonic enhancement to dot-to-dot variations, measurements were performed on the same dot at different stages of the sample processing, enabled by the use of a novel site-controlled InGaN QD structure. This was then repeated over a large number of dots and compared between different metal materials to investigate the nature of the coupling.