Continuous distribution of emission states from single CdSe/ZnS quantum dots.
The photoluminescence dynamics of colloidal CdSe/ZnS/streptavidin quantum dots were studied using time-resolved single-molecule spectroscopy. Statistical tests of the photon-counting data suggested that the simple "on/off" discrete state model is inconsistent with experimental results. Instead, a continuous emission state distribution model was found to be more appropriate. Autocorrelation analysis of lifetime and intensity fluctuations showed a nonlinear correlation between them. These results were consistent with the model that charged quantum dots were also emissive, and that time-dependent charge migration gave rise to the observed photoluminescence dynamics.
Zhang
Kai
K
Department of Chemistry, University of California, Berkeley, California 94720, USA.
Chang
Hauyee
H
Fu
Aihua
A
Alivisatos
A Paul
AP
Yang
Haw
H
D019187:Cadmium Compounds / Q000737:chemistry* / Q000528:radiation effects; D003198:Computer Simulation; D008027:Light; D008163:Luminescent Measurements; D008422:Materials Testing; D008956:Models, Chemical; D045663:Quantum Dots; D018036:Selenium Compounds / Q000737:chemistry* / Q000528:radiation effects; D013440:Sulfides / Q000737:chemistry* / Q000528:radiation effects; D017967:Zinc Compounds / Q000737:chemistry* / Q000528:radiation effects
D019187:Cadmium Compounds; D018036:Selenium Compounds; D013440:Sulfides; D017967:Zinc Compounds; C058667:cadmium selenide; C031238:zinc sulfide