Correlated spontaneous emission of fluorescent emitters mediated by single plasmons

TL;DR

This paper demonstrates correlated emission between a quantum dot and a fluorescent nanobead mediated by a silver nanowire, showing a step towards plasmon-mediated coupling of quantum emitters.

Contribution

It reports the first observation of correlated emission between two separate emitters via plasmonic coupling using a silver nanowire.

Findings

Correlated emission observed between quantum dot and nanobead.

Coupling mediated by single plasmons on a silver nanowire.

First demonstration of plasmon-mediated emitter-emitter correlation.

Abstract

Manipulating the spontaneous emission of a fluorescent emitter can be achieved by placing the emitter in a nanostructured environment. A privileged spot is occupied by plasmonic structures that provide a strong confinement of the electromagnetic field, which results in an enhancement of the emitter-environment interaction. While plasmonic nanostructures have been widely exploited to control the emission properties of single photon emitters, performing the coupling between quantum emitters with plasmons poses a huge challenge. In this Letter we report on a first crucial step towards this goal by the observation of correlated emission between a single CdSe/CdS/ZnS quantum dot exhibiting single photon statistics and a fluorescent nanobead located micrometers apart. This is accomplished by coupling both emitters to a silver nanowire. Single-plasmons are created on the latter from the quantum dot, and transfer energy to excite in turn the fluorescent nanobead.