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arXiv · 1611.03455

Doping driven metal-insulator transitions and charge orderings in the extended Hubbard model

K. J. Kapcia·S. Robaszkiewicz·M. Capone·A. Amaricci
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Abstract

We perform a thorough study of an extended Hubbard model featuring local and nearest-neighbor Coulomb repulsion. Using dynamical mean-field theory we investigated the zero temperature phase-diagram of this model as a function of the chemical doping. The interplay between local and non-local interaction drives a variety of phase-transitions connecting two distinct charge-ordered insulators, i.e., half-filled and quarter-filled, a charge-ordered metal and a Mott insulating phase. We characterize these transitions and the relative stability of the solutions and we show that the two interactions conspire to stabilize the quarter-filled charge ordered phase.

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K. J. Kapcia, S. Robaszkiewicz, M. Capone, A. Amaricci. 2016-11-10. Doping driven metal-insulator transitions and charge orderings in the extended Hubbard model. https://doi.org/10.1103/physrevb.95.125112

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