Photon antibunching in single CdSe/ZnS quantum dot fluorescence

摘要

We investigate the fluorescence intensity correlation function of a single CdSe quantum dot(QD) using a start-stop experiment.We observe strong photon antibunching,a signature of non-classical light emission,over a large range of intensities (0.1-100kW/cm~2).The lack of coincidence at zero time delay indicates a highly efficient Auger ionization process,which suppresses multi-photon emission in these colloidal QDs.Using careful analysis of the saturation behaviour of the coincidence histograms,the absorption cross-section of a single QD has also been derived.