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Intermediate Coupling Theory of Electronic Ferroelectricity

C. D. Batista·J. E. Gubernatis·J. Bonča·H. Q. Lin
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Abstract

We calculate the quantum phase diagram of an extended Falicov-Kimball model for one and two-dimensional systems in the intermediate coupling regime. Even though some features of the phase diagram are obtained analytically, the main results are calculated with a constrained path Monte Carlo technique. We find that this regime is dominated by a Bose-Einstein condensation of excitons with a built-in electric polarization. The inclusion of a finite hybridization between the bands removes the condensate but reinforces the ferroelectricity.

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C. D. Batista, J. E. Gubernatis, J. Bonča, H. Q. Lin. 2004-02-26. Intermediate Coupling Theory of Electronic Ferroelectricity. https://doi.org/10.1103/physrevlett.92.187601

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