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Dispersion of a single $4f$ impurity state in photoemission spectra of Yb/W(110)

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 نشر من قبل Yu. S. Dedkov
 تاريخ النشر 2008
  مجال البحث فيزياء
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Angle-resolved photoemission spectra of a monolayer of Yb on W(110) reveal energy splittings and dispersion of the Yb 4f states that are obviously due to their hybridization with W-derived valence bands. These effects occur at well defined points of the surface Brillouin zone although a smearing over reciprocal space is expected from the structural incoherence of the Yb and W lattices. We conclude therefore that dispersion is not related to the periodic arrangement of the $4f$ states but reflects the k-dependent interaction of a single Yb 4f impurity with W bands.



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