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Signatures of spin pairing in a quantum dot in the Coulomb blockade regime

S. Luescher·T. Heinzel·K. Ensslin·W. Wegscheider·M. Bichler
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Abstract

Coulomb blockade resonances are measured in a GaAs quantum dot in which both shape deformations and interactions are small. The parametric evolution of the Coulomb blockade peaks shows a pronounced pair correlation in both position and amplitude, which is interpreted as spin pairing. As a consequence, the nearest-neighbor distribution of peak spacings can be well approximated by a smeared bimodal Wigner surmise, provided that interactions which go beyond the constant interaction model are taken into account.

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S. Luescher, T. Heinzel, K. Ensslin, W. Wegscheider, M. Bichler. 2000-02-15. Signatures of spin pairing in a quantum dot in the Coulomb blockade regime. https://doi.org/10.1103/physrevlett.86.2118

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