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Exploring the exotic f states of prototype compounds CeSb and USb

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 نشر من قبل Haiyan Lu
 تاريخ النشر 2019
  مجال البحث فيزياء
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To unravel the interplay between the strong electronic correlation and itinerant-localized dual nature in atypical f electron systems, we employed the density functional theory in combination with the single-site dynamical mean-field theory to systematically investigate the electronic structures of CeSb and USb. We find that the 4f states in CeSb are mostly localized which show a weak quasi-particle resonance peak near the Fermi level. Conversely, the 5f electrons in USb display partially itinerant feature, accompanied by mixed-valence behavior and prominent valence state fluctuations. Particularly, the 4f electronic correlations in CeSb are distinctly orbital-selective with strikingly renormalized 4f5/2 states, according to the low-energy behaviors of 4f self-energy functions. It is believed that the strong electronic correlation and fantastic bonding of f states contribute to elucidate the fascinating magnetism.



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