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arXiv · 1204.4900

Low-energy models for correlated materials: bandwidth renormalization from Coulombic screening

M. Casula·Ph. Werner·L. Vaugier·F. Aryasetiawan·A. J. Millis·S. Biermann
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Abstract

We provide a prescription for constructing Hamiltonians representing the low energy physics of correlated electron materials with dynamically screened Coulomb interactions. The key feature is a renormalization of the hopping and hybridization parameters by the processes that lead to the dynamical screening. The renormalization is shown to be non-negligible for various classes of correlated electron materials. The bandwidth reduction effect is necessary for connecting models to materials behavior and for making quantitative predictions for low-energy properties of solids.

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M. Casula, Ph. Werner, L. Vaugier, F. Aryasetiawan, A. J. Millis, S. Biermann. 2012-04-22. Low-energy models for correlated materials: bandwidth renormalization from Coulombic screening. https://doi.org/10.1103/physrevlett.109.126408

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