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arXiv · 1311.5503

Magnetic field induced shell-to-core confinement transition in type-II semiconductor quantum wires

R. Macêdo·J. Costa e Silva·Andrey Chaves·G. A. Farias·R. Ferreira
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Abstract

We investigate the excitonic properties of a core-multishell semiconductor nanowire with type-II band mismatch, i.e. with spatially separated electrons and holes, under an external magnetic field. Our results demonstrate that, depending on the core wire radius, the carrier in the type-II band exhibits either a quantum dot-like or a quantum ring-like energy spectrum, corresponding to a carrier confinement in the core wire or in the outer shell, respectively. In the latter, a shell-to-core confinement transition can be induced by increasing the magnetic field intensity, which may lead to interesting photocurrent properties of these confining structures, tunable by the external field.

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R. Macêdo, J. Costa e Silva, Andrey Chaves, G. A. Farias, R. Ferreira. 2013-11-21. Magnetic field induced shell-to-core confinement transition in type-II semiconductor quantum wires. https://doi.org/10.1063/1.4802588

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