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Electronic polarons in an extended Falicov-Kimball model

P. M. R. Brydon·M. Gulacsi·A. R. Bishop
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Abstract

We examine the one-dimensional spinless Falicov-Kimball model extended by a hybridization potential between the localized and itinerant electron states. Below half-filling we find a crossover from a mixed-valence metal to an integer-valence phase separated state with increasing on-site Coulomb repulsion. This crossover regime is characterized by local competition between the strong- and weak-coupling behaviour, manifested by the formation of an electronic polaron liquid. We identify this intermediate-coupling regime as a charge-analogy of the Griffiths phase; a phase diagram is presented and discussed in detail.

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P. M. R. Brydon, M. Gulacsi, A. R. Bishop. 2005-11-22. Electronic polarons in an extended Falicov-Kimball model. https://doi.org/10.1209/epl%2Fi2005-10509-0

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