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arXiv · 0911.2200

Transport properties of quantum dots in the Wigner molecule regime

F. Cavaliere·U. De Giovannini·M. Sassetti·B. Kramer
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Abstract

The transport properties of quantum dots with up to N=7 electrons ranging from the weak to the strong interacting regime are investigated via the projected Hartree-Fock technique. As interactions increase radial order develops in the dot, with the formation of ring and centered-ring structures. Subsequently, angular correlations appear, signalling the formation of a Wigner molecule state. We show striking signatures of the emergence of Wigner molecules, detected in transport. In the linear regime, conductance is exponentially suppressed as the interaction strength grows. A further suppression is observed when centered-ring structures develop, or peculiar spin textures appear. In the nonlinear regime, the formation of molecular states may even lead to a conductance enhancement.

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F. Cavaliere, U. De Giovannini, M. Sassetti, B. Kramer. 2009-11-11. Transport properties of quantum dots in the Wigner molecule regime. https://doi.org/10.1088/1367-2630/11/12/123004

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