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Momentum distribution functions in a one-dimensional extended periodic Anderson model

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 نشر من قبل Imre Hagymasi
 تاريخ النشر 2015
  مجال البحث فيزياء
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We study the momentum distribution of the electrons in an extended periodic Anderson model, where the interaction, $U_{cf}$, between itinerant and localized electrons is taken into account. In the symmetric half-filled model, due to the increase of the interorbital interaction, the $f$ electrons become more and more delocalized, while the itinerancy of conduction electrons decreases. Above a certain value of $U_{cf}$ the $f$ electrons become again localized together with the conduction electrons. In the less than half-filled case, we observe that $U_{cf}$ causes strong correlations between the $f$ electrons in the mixed valence regime.

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