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Multiband theory of quantum-dot quantum wells: Dark excitons, bright excitons, and charge separation in heteronanostructures

W. Jaskolski·Garnett W. Bryant
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Abstract

Electron, hole, and exciton states of multishell CdS/HgS/CdS quantum-dot quantum well nanocrystals are determined by use of a multiband theory that includes valence-band mixing, modeled with a 6-band Luttinger-Kohn Hamiltonian, and nonparabolicity of the conduction band. The multiband theory correctly describes the recently observed dark-exciton ground state and the lowest, optically active, bright-exciton states. Charge separation in pair states is identified. Previous single-band theories could not describe these states or account for charge separation.

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W. Jaskolski, Garnett W. Bryant. 1997-09-17. Multiband theory of quantum-dot quantum wells: Dark excitons, bright excitons, and charge separation in heteronanostructures. https://doi.org/10.1103/physrevb.57.r4237

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