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arXiv · 1010.2040

Competing chiral and multipolar electric phases in the extended Falicov-Kimball model

B. Zenker·H. Fehske·C. D. Batista
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Abstract

We study the effects of interband hybridization within the framework of an extended Falicov-Kimball model with itinerant $c$ and $f$ electrons. An explicit interband hybridization breaks the U(1) symmetry associated with the conservation of the difference between the total number of particles in each band. As a result, the degeneracy between multipolar electric and chiral orderings is lifted. We analyze the weak- and strong-coupling limits of the $c$-$f$ electron Coulomb interaction at zero temperature, and derive the corresponding mean-field quantum phase diagrams at half-filling for a model defined on a square lattice.

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B. Zenker, H. Fehske, C. D. Batista. 2010-10-11. Competing chiral and multipolar electric phases in the extended Falicov-Kimball model. https://doi.org/10.1103/physrevb.82.165110

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