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Kondo-excitons and Auger processes in self-assembled quantum dots

A. O. Govorov·K. Karrai·R. J. Warburton·A. V. Kalameitsev
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Abstract

We describe theoretically novel excitons in self-assembled quantum dots interacting with a two-dimensional electron gas in the wetting layer. In the presence of the Fermi sea, the optical lines become strongly voltage-dependent. If the electron spin is nonzero, the width of optical lines is given by k_BT_K, where T_K is Kondo temperature. If the spin is zero, the exciton couples with the continuum due to Auger-like processes. This leads to anticrossings in a magnetic field. Some of the described phenomena are observed in recent experiments.

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A. O. Govorov, K. Karrai, R. J. Warburton, A. V. Kalameitsev. 2003-02-16. Kondo-excitons and Auger processes in self-assembled quantum dots. https://arxiv.org/abs/cond-mat/0302317

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