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Multi-excitons in self-assembled InAs/GaAs quantum dots: A pseudopotential, many-body approach

A. J. Williamson·A. Franceschetti·A. Zunger
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Abstract

We use a many-body, atomistic empirical pseudopotential approach to predict the multi-exciton emission spectrum of a lens shaped InAs/GaAs self-assembled quantum dot. We discuss the effects of (i) The direct Coulomb energies, including the differences of electron and hole wavefunctions, (ii) the exchange Coulomb energies and (iii) correlation energies given by a configuration interaction calculation. Emission from the groundstate of the $N$ exciton system to the $N-1$ exciton system involving $e_0\to h_0$ and $e_1\to h_1$ recombinations are discussed. A comparison with a simpler single-band, effective mass approach is presented.

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A. J. Williamson, A. Franceschetti, A. Zunger. 2000-06-06. Multi-excitons in self-assembled InAs/GaAs quantum dots: A pseudopotential, many-body approach. https://doi.org/10.1209/epl%2Fi2001-00123-2

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