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arXiv · 1304.1745

Nonequilibrium dynamics in an optical transition from a neutral quantum dot to a correlated many-body state

F. Haupt·S. Smolka·M. Hanl·W. Wüster·J. Miguel-Sanchez·A. Weichselbaum·J. von Delft·A. Imamoglu
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Abstract

We investigate the effect of many-body interactions on the optical absorption spectrum of a charge-tunable quantum dot coupled to a degenerate electron gas. A constructive Fano interference between an indirect path, associated with an intra dot exciton generation followed by tunneling, and a direct path, associated with the ionization of a valence-band quantum dot electron, ensures the visibility of the ensuing Fermi-edge singularity despite weak absorption strength. We find good agreement between experiment and renormalization group theory, but only when we generalize the Anderson impurity model to include a static hole and a dynamic dot-electron scattering potential. The latter highlights the fact that an optically active dot acts as a tunable quantum impurity, enabling the investigation of a new dynamic regime of Fermi-edge physics.

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F. Haupt, S. Smolka, M. Hanl, W. Wüster, J. Miguel-Sanchez, A. Weichselbaum, J. von Delft, A. Imamoglu. 2013-11-04. Nonequilibrium dynamics in an optical transition from a neutral quantum dot to a correlated many-body state. https://doi.org/10.1103/physrevb.88.161304

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