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Quantized electronic fine structure with large anisotropy in ferromagnetic Fe films

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 نشر من قبل Hendrik Bentmann
 تاريخ النشر 2015
  مجال البحث فيزياء
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We report on the spectroscopic observation of a quantized electronic fine structure near the Fermi energy in thin Fe films grown on W(110). The quantum well states are detected down to binding energies of $sim$10 meV by angle-resolved photoelectron spectroscopy. The band dispersion of these states is found to feature a pronounced anisotropy within the surface plane: It is free-electron like along the $bar{Gamma rm{H}}$-direction while it becomes heavy along $bar{Gamma rm{N}}$. Density functional theory calculations identify the observed states to have both majority and minority spin character and indicate that the large anisotropy can be dependent on the number of Fe-layers and coupling to the substrate.

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