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arXiv · 0903.0497

Dark exciton optical spectroscopy of a semiconducting quantum dot embedded in a nanowire

Gregory Sallen·Adrien Tribu·Thomas Aichele·Régis André·Lucien Besombes·Catherine Bougerol-Chaillout·Serge Tatarenko·Kuntheak Kheng·Jean-Philippe Poizat
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Abstract

Photoluminescence of a single CdSe quantum dot embedded in a ZnSe nanowire has been investigated. It has been found that the dark exciton has a strong influence on the optical properties. The most visible influence is the strongly reduced excitonic emission compared to the biexcitonic one. Temperature dependent lifetime measurements have allowed us to measure a large splitting of $\Delta E = 6 $ meV between the dark and the bright exciton as well as the spin flip rates between these two states.

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Gregory Sallen, Adrien Tribu, Thomas Aichele, Régis André, Lucien Besombes, Catherine Bougerol-Chaillout, Serge Tatarenko, Kuntheak Kheng, Jean-Philippe Poizat. 2009-03-03. Dark exciton optical spectroscopy of a semiconducting quantum dot embedded in a nanowire. https://doi.org/10.1103/physrevb.80.085310

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