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Combined GW and dynamical mean field theory: Dynamical screening effects in transition metal oxides

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 نشر من قبل Jan M. Tomczak
 تاريخ النشر 2012
  مجال البحث فيزياء
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We present the first dynamical implementation of the combined GW and dynamical mean field scheme (GW+DMFT) for first principles calculations of the electronic properties of correlated materials. The application to the ternary transition metal oxide SrVO3 demonstrates that this schemes inherits the virtues of its two parent theories: a good description of the local low energy correlation physics encoded in a renormalized quasi-particle band structure, spectral weight transfer to Hubbard bands, and the physics of screening driven by long-range Coulomb interactions. Our data is in good agreement with available photoemission and inverse photoemission spectra; our analysis leads to a reinterpretation of the commonly accepted three-peak structure as originating from orbital effects rather than from the electron addition peak within the t2g manifold.

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