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arXiv · 1810.07598

Pressure induced valence and metal-insulator transitions in the Falicov-Kimball model with nonlocal hybridization

Pavol Farkasovsky
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Abstract

We present a simple, but very realistic, model for a description of pressure induced valence and metal-insulator transitions in mixed valence systems. It is based on the extended Falicov-Kimball model and the supposition that the key interaction governing these transitions is the nonlocal hybridization between the localized $f$ and itinerant $d$ electrons. Taking into account, in addition, the~parametrization between the external pressure and the $d$-$f$ hybridization (the experimental fact), the model is able to describe, at least qualitatively, valence as well as metal-insulator transitions driven by the external pressure observed experimentally in some rare-earth systems, like SmB$_6$.

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Pavol Farkasovsky. 2018-10-17. Pressure induced valence and metal-insulator transitions in the Falicov-Kimball model with nonlocal hybridization. https://doi.org/10.1016/j.ssc.2018.10.012

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