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Electronic phase transitions in the half-filled ionic Hubbard model

L. Craco·P. Lombardo·R. Hayn·G. I. Japaridze·E. Müller-Hartmann
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Abstract

A detailed study of electronic phase transitions in the ionic Hubbard model at half filling is presented. Within the dynamical mean field approximation a series of transitions from the band insulator via a metallic state to a Mott-Hubbard insulating phase is found at intermediate values of the one-body potential $Δ$ with increasing the Coulomb interaction $U$. We obtain a critical region in which the metallic phase disappears and a {\it novel} coexistence phase between the band and the Mott insulating state sets in. Our results are consistent with those obtained at low dimensions, thus they provide a concrete description for the charge degrees of freedom of the ionic Hubbard model.

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L. Craco, P. Lombardo, R. Hayn, G. I. Japaridze, E. Müller-Hartmann. 2007-09-26. Electronic phase transitions in the half-filled ionic Hubbard model. https://doi.org/10.1103/physrevb.78.075121

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