Coherent photonic coupling of semiconductor quantum dots

Technishe Physik, Universität Würzburg, Germany.
Optics Letters (Impact Factor: 3.18). 07/2006; 31(11):1738-40. DOI: 10.1364/OL.31.001738
Source: PubMed

ABSTRACT We report a new type of coupling between quantum dot excitons mediated by the strong single-photon field in a high-finesse micropillar cavity. Coherent exciton coupling is observed for two dots with energy differences of the order of the exciton-photon coupling. The coherent coupling mode is characterized by an anticrossing with a particularly large line splitting of 250 microeV. Because of the different dispersion relations with temperature, the simultaneous photonic coupling of quantum dot excitons can be easily distinguished from cases of sequential strong coupling of two quantum dots.

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