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Detection of Coulomb Charging around an Antidot in the Quantum Hall Regime

M. Kataoka·C. J. B. Ford·G. Faini·D. Mailly·M. Y. Simmons·D. R. Mace·C. -T. Liang·D. A. Ritchie
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Abstract

We have detected oscillations of the charge around a potential hill (antidot) in a two-dimensional electron gas as a function of a large magnetic field B. The field confines electrons around the antidot in closed orbits, the areas of which are quantised through the Aharonov-Bohm effect. Increasing B reduces each state's area, pushing electrons closer to the centre, until enough charge builds up for an electron to tunnel out. This is a new form of the Coulomb blockade seen in electrostatically confined dots. Addition and excitation spectra in DC bias confirm the Coulomb blockade of tunnelling.

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M. Kataoka, C. J. B. Ford, G. Faini, D. Mailly, M. Y. Simmons, D. R. Mace, C. -T. Liang, D. A. Ritchie. 1999-07-29. Detection of Coulomb Charging around an Antidot in the Quantum Hall Regime. https://doi.org/10.1103/physrevlett.83.160

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