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Renormalization of Bulk Magnetic Electron States at High Binding Energies

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 نشر من قبل Joerg Schaefer
 تاريخ النشر 2009
  مجال البحث فيزياء
والبحث باللغة English
 تأليف A. Hofmann




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The quasiparticle dynamics of electrons in a magnetically ordered state is investigated by high-resolution angle-resolved photoemission of Ni(110) at 10 K. The self-energy is extracted for high binding energies reaching up to 500 meV, using a Gutzwiller calculation as a reference frame for correlated quasiparticles. Significant deviations exist in the 300 meV range, as identified on magnetic bulk bands for the first time. The discrepancy is strikingly well described by a self-energy model assuming interactions with spin excitations. Implications relating to different electron-electron correlation regimes are discussed.

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