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arXiv · 0911.2060

Correlation-induced conductance suppression at level degeneracy in a quantum dot

H. A. Nilsson·O. Karlström·M. Larsson·P. Caroff·J. N. Pedersen·L. Samuelson·A. Wacker·L. E. Wernersson·H. Q. Xu
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Abstract

The large, level-dependent g-factors in an InSb nanowire quantum dot allow for the occurrence of a variety of level crossings in the dot. While we observe the standard conductance enhancement in the Coulomb blockade region for aligned levels with different spins due to the Kondo effect, a vanishing of the conductance is found at the alignment of levels with equal spins. This conductance suppression appears as a canyon cutting through the web of direct tunneling lines and an enclosed Coulomb blockade region. In the center of the Coulomb blockade region, we observe the predicted correlation-induced resonance, which now turns out to be part of a larger scenario. Our findings are supported by numerical and analytical calculations.

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H. A. Nilsson, O. Karlström, M. Larsson, P. Caroff, J. N. Pedersen, L. Samuelson, A. Wacker, L. E. Wernersson, H. Q. Xu. 2010-05-06. Correlation-induced conductance suppression at level degeneracy in a quantum dot. https://doi.org/10.1103/physrevlett.104.186804

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