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arXiv · 1005.3556

Extended Hubbard model: Charge Ordering and Wigner-Mott transition

Adriano Amaricci·Alberto Camjayi·Darko Tanaskovic·Kristjan Haule·Vladimir Dobrosavljevic·Gabriel Kotliar
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Abstract

Strong correlation effects, which are often associated to the approach to a Mott insulating state, in some cases may be observed even far from half-filling. This typically happens whenever the inter-site Coulomb repulsion induces a tendency towards charge ordering, an effect that confines the electrons, and in turn favors local moment formation, i.e. Mott localization. A distinct intermediate regime then emerges as a precursor of such a Wigner-Mott transition, which is characterized by both charge and spin correlations, displaying large mass enhancements and strong renormalizations of other Fermi liquid parameters. Here we present a careful study of a quarter filled extended Hubbard model - a simple example where such physics can be studied in detail, and discuss its relevance for the understanding of the phenomenology of low-density two dimensional electron gases.

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Adriano Amaricci, Alberto Camjayi, Darko Tanaskovic, Kristjan Haule, Vladimir Dobrosavljevic, Gabriel Kotliar. 2010-05-19. Extended Hubbard model: Charge Ordering and Wigner-Mott transition. https://doi.org/10.1103/physrevb.82.155102

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