Nonexponential Blinking Kinetics of Single CdSe Quantum Dots: A Universal Power Law Behavior

Published

February 1, 2000

Author(s)

M Kuno, D P. Fromm, H F. Hamann, Alan Gallagher, David Nesbitt

Abstract

We have studied the fluorescence intermittency of single CdSe quantum dots (17-29 radius) overcoated with ZnS. Optical measurements were made using a confocal microscope under epillumination conditions, with the 488 nm line of an Ar⁺ laser as the excitation source. This excitation was focused to a nearly diffraction-limited spot on the surface of a suprasil prism onto which the sample has been spin cast. Emission from the sample was collected through the same objective. The emission was then focused into a multimode fiber and directed to an avalanche photodiode (APD). Fluorescence intensity vs. time traces were obtained and integration times sampled. The net optical collection efficiencyof the system (i.e., number of fluorescence photons emitted versus photon counts registered on the APD) has been determined to be approximately 1-2%.

Citation

Journal of Chemical Physics

Volume

112

Issue

No. 7

Pub Type

Journals

Keywords

blinking kinetics, fluorescence, intermittency, power law, quantum dot, single molecule

Citation

Kuno, M. , Fromm, D. , Hamann, H. , Gallagher, A. and Nesbitt, D. (2000), Nonexponential Blinking Kinetics of Single CdSe Quantum Dots: A Universal Power Law Behavior, Journal of Chemical Physics (Accessed December 7, 2024)