Time resolved fluorescence of CdSe nanocrystals using single molecule spectroscopy

A wide variety of spectroscopic studies of CdSe nanocrystals (NCs) are presented in this thesis, all studying some aspect of the temporal evolution of NC fluorescence tinder different conditions. In particular the methods of single molecule spectroscopy are used in many experiments allowing the behavior of individual NCs to be resolved from the blurring effect of averaging over the ensemble. Studies of the excited state lifetime of band edge fluorescence from single NCs reveal multiexponential relaxation dynamics that stem from fluctuations of non-radiative decay rates for the band edge exciton. Analysis of these fluctuations allows us to extract single exponential dynamics by sampling only "maximum-intensity" photons, and we find that this single exponential decay is remarkably uniform across a wide variety of NC samples and sizes. We also investigate luminescence from multiexciton (e.g. biexciton and triexciton) states of nanocrystals at both the ensemble and single NC level.

Department dc:contributor.department

Massachusetts Institute of Technology. Dept. of Chemistry.

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2005

Author dc:creator

• Fisher, Brent R

Advisor dc:contributor.advisor

• Moungi G. Bawendi.

• Chemistry.

Statement dc:rights

• M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/1721.1/33649

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/33649