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Single-Electron Effects in a Coupled Dot-Ring System

L. Meier·A. Fuhrer·T. Ihn·K. Ensslin·W. Wegscheider·M. Bichler
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Abstract

Aharonov-Bohm oscillations are studied in the magnetoconductance of a micron-sized open quantum ring coupled capacitively to a Coulomb-blockaded quantum dot. As the plunger gate of the dot is modulated and tuned through a conductance resonance, the amplitude of the Aharonov-Bohm oscillations in the transconductance of the ring displays a minimum. We demonstrate that the effect is due to a single-electron screening effect, rather than to dephasing. Aharonov-Bohm oscillations in a quantum ring can thus be used for the detection of single charges.

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L. Meier, A. Fuhrer, T. Ihn, K. Ensslin, W. Wegscheider, M. Bichler. 2004-06-04. Single-Electron Effects in a Coupled Dot-Ring System. https://doi.org/10.1103/physrevb.69.241302

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