Photoluminescence enhancement of the single InAs quantum dots through plasmonic Au island films

The approach of optical positioning the single InAs quantum dots (QDs) was used for investigating QD photoluminescence (PL) enhancement based on plasmonic effect of nanometer-sized Au island films. It is found that the maximum increase of QD PL intensity is about thirty-eight fold after 5-nm thick Au island films are evaporated on the QD sample surface. The enhanced localized excitation field and increased QD radiative decay rate are responsible for this PL enhancement. This provides an alternative way of preparing bright single photon sources based on the plasmonic effect