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

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 نشر من قبل Michele Casula
 تاريخ النشر 2012
  مجال البحث فيزياء
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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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