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Single-electron charging and detection in a laterally-coupled quantum dot circuit in the few-electron regime

L. -X. Zhang·P. Matagne·J. P. Leburton·R. Hanson·L. P. Kouwenhoven
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Abstract

We provide a physical analysis of the charging and detection of the first few electrons in a laterally-coupled GaAs/AlGaAs quantum dot (LCQD) circuit with integrated quantum point contact (QPC) read-out. Our analysis is based on the numerical solution of the Kohn-Sham equation incorporated into a three-dimensional self-consistent scheme for simulating the quantum device. Electronic states and eigenenergy spectra reflecting the particular LCQD confinement shape are obtained as a function of external gate voltages. We also derive the stability diagram for the first few electrons in the device, and obtain excellent agreement with experimental data.

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L. -X. Zhang, P. Matagne, J. P. Leburton, R. Hanson, L. P. Kouwenhoven. 2003-11-03. Single-electron charging and detection in a laterally-coupled quantum dot circuit in the few-electron regime. https://doi.org/10.1103/physrevb.69.245301

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