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arXiv · 1407.6585

Charge tuning in [111] grown GaAs droplet quantum dots

L. Bouet·M. Vidal·T. Mano·N. Ha·T. Kuroda·M. V. Durnev·M. M. Glazov·E. L. Ivchenko·X. Marie·T. Amand·K. Sakoda·G. Wang·B. Urbaszek
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Abstract

We demonstrate charge tuning in strain free GaAs/AlGaAs quantum dots (QDs) grown by droplet epitaxy on a GaAs(111)A substrate. Application of a bias voltage allows the controlled charging of the QDs from $-3|e|$ to $+2|e|$. The resulting changes in QD emission energy and exciton fine-structure are recorded in micro-photoluminescence experiments at T=4K. We uncover the existence of excited valence and conduction states, in addition to the s-shell-like ground state. We record a second series of emission lines about 25meV above the charged exciton emission coming from excited charged excitons. For these excited interband transitions a negative diamagnetic shift of large amplitude is uncovered in longitudinal magnetic fields.

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L. Bouet, M. Vidal, T. Mano, N. Ha, T. Kuroda, M. V. Durnev, M. M. Glazov, E. L. Ivchenko, X. Marie, T. Amand, K. Sakoda, G. Wang, B. Urbaszek. 2014-07-24. Charge tuning in [111] grown GaAs droplet quantum dots. https://doi.org/10.1063/1.4894174

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