Plasmon assisted single photon emission of CdSe/CdS nanocrystals deposited on random gold film

We have investigated the modifications of the fluorescence properties of single CdSe/CdS nanocrystals deposited close to a semicontinuous gold film. We report a reduction by a factor of ten of the monoexcitonic state decay rate. Due to the structure of the plasmon resonances, the decay depends on the nanocrystal position. Through the detailed study of the collection efficiency, we show that a large fraction of the plasmons are converted in far field single photons. These results demonstrate the great interest of plasmonic devices to control the single photon emission of colloidal nanocrystals.