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arXiv · 0704.1389

Gutzwiller description of non-magnetic Mott insulators: a dimer lattice model

Michele Fabrizio
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Abstract

We introduce a novel extension of the Gutzwiller variational wavefunction able to deal with insulators that escape any mean-field like description, as for instance non-magnetic insulators. As an application, we study the Mott transition from a paramagnetic metal into a non-magnetic Peierls, or valence-bond, Mott insulator. We analyze this model by means of our Gutzwiller wavefunction analytically in the limit of large coordination lattices, where we find that: (1) the Mott transition is first order; (2) the Peierls gap is large in the Mott insulator, although it is mainly contributed by the electron repulsion; (3) singlet-superconductivity arises around the transition.

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Michele Fabrizio. 2007-04-11. Gutzwiller description of non-magnetic Mott insulators: a dimer lattice model. https://doi.org/10.1103/physrevb.76.165110

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