Coupling of spontaneous emission from GaN–AlN quantum dots into silver surface plasmons

We have demonstrated the decay of spontaneous emission (SE) from AlN–GaN quantum dots (QDs) into silver surface plasmon (SP) modes in the ultraviolet at approximately 375–380 nm. Using time-resolved photoluminescence (PL), we show that the electron–hole recombination rate in AlN–GaN QDs is enhanced when SE is resonantly coupled to a metal SP mode, corresponding to the dip in the continuous-wave PL spectrum. Exciton recombination by means of silver SP modes is as much as 3–7 times faster than in normal QD SE and depends strongly on emission wavelength and thickness of the silver.