Early, K. T. and McCarthy, K. D. and Odoi, M. Y. and Sudeep, P. K. and Emrick, T. and Barnes, M. D.. (2009) Linear Dipole Behavior in Single CdSe-Oligo(phenylene vinylene) Nanostructures. ACS Nano, 3 (2). pp. 453-461. ISSN 1936-0851
Full text not available from this repository. (Request a copy)Abstract
We report on linearly polarized absorption and emission from individual (4.3 nm) CdSe quantum dots whose surfaces are coordinated with monodisperse oligo-phenylene vinylene ligands. Shown previously to suppress quantum dot blinking, we demonstrate here that the electronic interaction of photoexcited ligands with the quantum dot core is manifested as a strong polarization anisotropy in absorption (M = 0.5), as well as distinct linear dipole emission patterns from the quantum dot core. Further, there is a correlation between the quantum dot emission moment and polarization orientation corresponding to the absorption maxima that is manifested as fluctuations in emission moment orientation in the X−Y plane. The observed polarization effects can be switched off by tuning the excitation away from the ligand absorption band. We propose a mechanism based on exciton dissociation from the photoexcited ligand, followed by the pinning of electrons at the quantum dot surface. The resulting Stark interaction is sufficiently strong to break the 2D degeneracy of the emission moment within the dot, and may therefore account for the linear dipole emission character.
Item Type: | Article |
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Additional Information: | Reprinted with permission from "Linear Dipole Behavior in Single CdSe-Oligo(phenylene vinylene) Nanostructures", K.T. Early et al. Copyright 2009 American Chemical Society." |
InterNano Taxonomy: | Nanoscale Objects and Nanostructured Materials Nanoscale Objects and Nanostructured Materials > Nanoparticles > Nanocrystals Informatics and Standards Nanomanufacturing Characterization Techniques > Other Characterization Techniques > Photoluminescence (PL) spectroscopy Nanoscale Objects and Nanostructured Materials > Nanoparticles > Quantum confinement |
Collections: | Nanomanufacturing Research Collection > Nanomanufacturing Nanoscale Science and Engineering Centers > Center for Hierarchical Manufacturing Nanomanufacturing Research Collection |
Depositing User: | Moureen Kemei |
Date Deposited: | 08 Feb 2010 20:08 |
Last Modified: | 19 Sep 2011 21:31 |
URI: | http://eprints.internano.org/id/eprint/264 |
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