Plasmon-enhanced Forster energy transfer between semiconductor quantum dots: multipole effects

We experimentally demonstrated plasmon-asssisted energy transfer (ET) between CdSe semiconductor quantum dots (QDs) self-assembled in a monolayer by using time-resolved mu-photoluminescence (PL) technique. The enhancements of PL intensity and ET efficiency were manipulated by adjusting thickness (Delta) of SiO2 coating on large Ag nanoparticles. The PL enhancement factor of the acceptor QDs and the PL intensity ratio of acceptor-to-donor reached their maxima similar to 47 and similar to 14 when Delta = 7 nm, the corresponding ET efficiency reached 86%. We also presented theoretical analysis based on the rate equation. The theoretical calculations agreed with experimental data and revealed interesting physics of multipole effect, and metal nanoparticle induced quench effect and plasmon-enhanced Forster ET. (C) 2010 Optical Society of America