Quantum-Confined Stark Effect in Single CdSe Nanocrystallite Quantum Dots
10.1126/science.278.5346.2114
Crossref journal-article
American Association for the Advancement of Science (AAAS)
Science (221)
Abstract

The quantum-confined Stark effect in single cadmium selenide (CdSe) nanocrystallite quantum dots was studied. The electric field dependence of the single-dot spectrum is characterized by a highly polarizable excited state (∼10 5 cubic angstroms, compared to typical molecular values of order 10 to 100 cubic angstroms), in the presence of randomly oriented local electric fields that change over time. These local fields result in spontaneous spectral diffusion and contribute to ensemble inhomogeneous broadening. Stark shifts of the lowest excited state more than two orders of magnitude larger than the linewidth were observed, suggesting the potential use of these dots in electro-optic modulation devices.

Bibliography

Empedocles, S. A., & Bawendi, M. G. (1997). Quantum-Confined Stark Effect in Single CdSe Nanocrystallite Quantum Dots. Science, 278(5346), 2114–2117.

Authors 2
  1. S. A. Empedocles (first)
  2. M. G. Bawendi (additional)
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  30. S.A.E. benefited from a Department of Defense graduate fellowship. This work was supported by the David and Lucile Packard Foundation and the Sloan Foundation. This research was funded in part by the NSF–Materials Research Science and Engineering Center program (DMR-94-00034). We thank the Massachusetts Institute of Technology Harrison Spectroscopy Laboratory (NSF-CHE-93-04251) for support and for allowing use of its facilities.
Dates
Type When
Created 23 years, 1 month ago (July 27, 2002, 5:37 a.m.)
Deposited 1 year, 7 months ago (Jan. 12, 2024, 11:55 p.m.)
Indexed 4 days, 13 hours ago (Aug. 27, 2025, 11:56 a.m.)
Issued 27 years, 8 months ago (Dec. 19, 1997)
Published 27 years, 8 months ago (Dec. 19, 1997)
Published Print 27 years, 8 months ago (Dec. 19, 1997)
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@article{Empedocles_1997, title={Quantum-Confined Stark Effect in Single CdSe Nanocrystallite Quantum Dots}, volume={278}, ISSN={1095-9203}, url={http://dx.doi.org/10.1126/science.278.5346.2114}, DOI={10.1126/science.278.5346.2114}, number={5346}, journal={Science}, publisher={American Association for the Advancement of Science (AAAS)}, author={Empedocles, S. A. and Bawendi, M. G.}, year={1997}, month=dec, pages={2114–2117} }