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Itinerancy and Electron Correlation in FeSe 1-x Superconductor Studied by Bulk-Sensitive Photoemission Spectroscopy

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 نشر من قبل Atsushi Yamasaki
 تاريخ النشر 2009
  مجال البحث فيزياء
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We have investigated the electronic structures of newly discovered superconductor FeSe1-x by bulk-sensitive photoemission spectroscopy (PES). The large Fe 3d spectral weight is located in the vicinity of the Fermi level (EF) and it decreases steeply toward EF . Compared with results of band structure calculations, narrowing the Fe 3d band width and the energy shift of the band toward EF are found, suggesting a mass enhancement due to the weak electron correlation effect. Meanwhile, Fe 2p core-level PES reveals a strong itinerant character of Fe 3d electrons. These features are very similar to those in other Fe-based high-Tc superconductors.



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