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arXiv · 1002.3114

Correlated electrons in optically-tunable quantum dots: Building an electron dimer molecule

Achintya Singha·Vittorio Pellegrini·Aron Pinczuk·Loren N. Pfeiffer·Ken W. West·Massimo Rontani
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Abstract

We observe the low-lying excitations of a molecular dimer formed by two electrons in a GaAs semiconductor quantum dot in which the number of confined electrons is tuned by optical illumination. By employing inelastic light scattering we identify the inter-shell excitations in the one-electron regime and the distinct spin and charge modes in the interacting few-body configuration. In the case of two electrons a comparison with configuration-interaction calculations allows us to link the observed excitations with the breathing mode of the molecular dimer and to determine the singlet-triplet energy splitting.

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Achintya Singha, Vittorio Pellegrini, Aron Pinczuk, Loren N. Pfeiffer, Ken W. West, Massimo Rontani. 2010-05-21. Correlated electrons in optically-tunable quantum dots: Building an electron dimer molecule. https://doi.org/10.1103/physrevlett.104.246802

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