Continuous distribution of emission states from single CdSe/ZnS quantum dots

Kai Zhang; Hauyee Chang; Aihua Fu; A Paul Alivisatos; Haw Yang

doi:10.1021/nl060483q

Continuous distribution of emission states from single CdSe/ZnS quantum dots

Nano Lett. 2006 Apr;6(4):843-7. doi: 10.1021/nl060483q.

Authors

Kai Zhang¹, Hauyee Chang, Aihua Fu, A Paul Alivisatos, Haw Yang

Affiliation

¹ Department of Chemistry, University of California, Berkeley, California 94720, USA.

PMID: 16608295
DOI: 10.1021/nl060483q

Abstract

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.

Publication types

Evaluation Study
Research Support, N.I.H., Extramural
Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

Cadmium Compounds / chemistry*
Cadmium Compounds / radiation effects
Computer Simulation
Light
Luminescent Measurements*
Materials Testing
Models, Chemical*
Quantum Dots*
Selenium Compounds / chemistry*
Selenium Compounds / radiation effects
Sulfides / chemistry*
Sulfides / radiation effects
Zinc Compounds / chemistry*
Zinc Compounds / radiation effects

Substances

Cadmium Compounds
Selenium Compounds
Sulfides
Zinc Compounds
cadmium selenide
zinc sulfide