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

Using time-resolved photoluminescence measurements, the recombination rate in an ${\mathrm{In}}_{0.18}{\mathrm{Ga}}_{0.82}\mathrm{N}/\mathrm{GaN}$ 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 QW spontaneous emission into free space. A calculation, based on Fermi’s golden rule, reveals that the enhancement is very sensitive to silver thickness and indicates even greater enhancements are possible for QW’s placed closer to the surface metal coating.