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arXiv · 0910.5138

Heterogeneous confinement in laterally coupled InGaAs/GaAs quantum dot molecules under lateral electric fields

Jie Peng·Claus Hermannstädter·Marcus Witzany·Matthias Heldmaier·Lijuan Wang·Suwit Kiravittaya·Armando Rastelli·Oliver G. Schmidt·Peter Michler·Gabriel Bester
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Abstract

We study the electronic and optical properties of laterally coupled InGaAs/GaAs quantum dot molecules under lateral electric field. We find that electrons perceive the double-dot structure as a compound single object, while the holes discern two well separated dots. Through a combination of predictive atomistic modeling, detailed morphology studies, and single object micro-photoluminescence measurements, we show that this peculiar confinement results in an unusual heterogeneous behavior of electrons and holes with profound consequences on optical properties.

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Jie Peng, Claus Hermannstädter, Marcus Witzany, Matthias Heldmaier, Lijuan Wang, Suwit Kiravittaya, Armando Rastelli, Oliver G. Schmidt, Peter Michler, Gabriel Bester. 2010-12-09. Heterogeneous confinement in laterally coupled InGaAs/GaAs quantum dot molecules under lateral electric fields. https://doi.org/10.1103/physrevb.81.205315

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