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Correlated Electrons Step-by-Step: Itinerant-to-Localized Transition of Fe Impurities in Free-Electron Metal Hosts

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 نشر من قبل A. Lichtenstein
 تاريخ النشر 2009
  مجال البحث فيزياء
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High-resolution photoemission spectroscopy and realistic ab-initio calculations have been employed to analyze the onset and progression of d-sp hybridization in Fe impurities deposited on alkali metal films. The interplay between delocalization, mediated by the free-electron environment, and Coulomb interaction among d-electrons gives rise to complex electronic configurations. The multiplet structure of a single Fe atom evolves and gradually dissolves into a quasiparticle peak near the Fermi level with increasing the host electron density. The effective multi-orbital impurity problem within the exact diagonalization scheme describes the whole range of hybridizations.

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