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Two-stage Kondo effect in a quantum dot at high magnetic field

W. G. van der Wiel·S. De Franceschi·J. M. Elzerman·S. Tarucha·L. P. Kouwenhoven·J. Motohisa·F. Nakajima·T. Fukui
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Abstract

We report a strong Kondo effect (Kondo temperature ~ 4K) at high magnetic field in a selective area growth semiconductor quantum dot. The Kondo effect is ascribed to a singlet-triplet transition in the ground state of the dot. At the transition, the low-temperature conductance approaches the unitary limit. Away from the transition, for low bias voltages and temperatures, the conductance is sharply reduced. The observed behavior is compared to predictions for a two-stage Kondo effect in quantum dots coupled to single-channel leads.

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W. G. van der Wiel, S. De Franceschi, J. M. Elzerman, S. Tarucha, L. P. Kouwenhoven, J. Motohisa, F. Nakajima, T. Fukui. 2001-10-20. Two-stage Kondo effect in a quantum dot at high magnetic field. https://doi.org/10.1103/physrevlett.88.126803

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