Surface plasmon polariton mediated photoluminescence from excitons in silicon nanocrystals

Surface plasmon polaritons (SPPs) of a metal film can efficiently be excited when a light emitter is placed nearby. The excited SPPs are converted to photons by compensating for the momentum mismatch. The authors study SPP-mediated emission from excitons in Si nanocrystals (Si-nc's) by placing an organic grating on a thin Au film placed near Si-nc's. The dispersion relation is obtained from angle-resolved photoluminescence measurements, and all the observed modes are well explained by model calculation. The results indicate that excitons in Si-nc's can efficiently excite SPPs in thin metal films and directed photoluminescence can be realized. (c) 2006 American Institute of Physics.