Excitation wavelength dependence of fluorescence intermittency in CdSe/ZnS core/shell quantum dots.
Core/shell CdSe/ZnS quantum dot fluorescence-blinking statistics depend strongly on excitation wavelength. Excitation on the band gap (575 nm) results in inverse-power law "on" time distributions. However, distributions resulting from excitation above the band gap (525 nm) require a truncated power law and are 100 times less likely to display 10-s fluorescence. "Off" time statistics are insensitive to the excitation wavelength. The results may be explained by nonemissive trap states accessed with the higher-photon excitation energies.
Knappenberger
Kenneth L
KL
Department of Chemistry, University of California and Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA.
Wong
Daryl B
DB
Romanyuk
Yaroslav E
YE
Leone
Stephen R
SR
D002104:Cadmium; D007700:Kinetics; D011789:Quantum Theory; D012643:Selenium; D013053:Spectrophotometry; D013455:Sulfur; D015032:Zinc
D002104:Cadmium; D013455:Sulfur; D012643:Selenium; D015032:Zinc