Enhancement of spontaneous emission in a quantum well by resonant surface plasmon coupling

TL;DR

This paper demonstrates that resonant coupling of spontaneous emission in an InGaN/GaN quantum well to surface plasmons on silver significantly accelerates emission rates, with potential for further enhancement by optimizing metal proximity.

Contribution

It provides experimental evidence and theoretical analysis showing how surface plasmon coupling can dramatically enhance quantum well emission rates.

Findings

Spontaneous emission rate increased up to 92 times due to plasmon coupling.

Enhancement is highly sensitive to silver layer thickness.

Closer placement of QWs to metal surface could yield greater emission enhancements.

Abstract

Using time-resolved photoluminescence measurements, the recombination rate in an In$_{0.18}$Ga$_{0.82}$N/GaN quantum well (QW) is shown to be greatly enhanced when spontaneous emission is resonantly coupled to a silver surface plasmon. The rate of enhanced spontaneous emission into the surface plasmon was as much as 92 times faster than normal QW spontaneous emission. A calculation, based on Fermi's golden rule, reveals the enhancement is very sensitive to silver thickness and indicates even greater enhancements are possible for QWs placed closer to the surface metal coating.