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Kondo Effect in a Quantum Antidot

M. Kataoka·C. J. B. Ford·M. Y. Simmons·D. A. Ritchie
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Abstract

We report Kondo-like behaviour in a quantum antidot (a submicron depleted region in a two-dimensional electron gas) in the quantum-Hall regime. When both spin branches of the lowest Landau level encircle the antidot in a magnetic field ($\sim 1$ T), extra resonances occur between extended edge states via antidot bound states when tunnelling is Coulomb blockaded. These resonances appear only in alternating Coulomb-blockaded regions, and become suppressed when the temperature or source-drain bias is raised. Although the exact mechanism is unknown, we believe that Kondo-like correlated tunnelling arises from skyrmion-type edge reconstruction. This observation demonstrates the generality of the Kondo phenomenon.

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M. Kataoka, C. J. B. Ford, M. Y. Simmons, D. A. Ritchie. 2002-10-03. Kondo Effect in a Quantum Antidot. https://doi.org/10.1103/physrevlett.89.226803

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