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Electron-phonon coupling and momentum-dependent electron dynamics in EuFe2As2 using time- and angle-resolved photoemission spectroscopy

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 نشر من قبل Laurenz Rettig
 تاريخ النشر 2010
  مجال البحث فيزياء
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The Fe pnictide parent compound EuFe2As2 exhibits a strongly momentum dependent carrier dynamics around the hole pocket at the center of the Brillouin zone. The very different dynamics of electrons and holes cannot be explained solely by intraband scattering and interband contributions have to be considered. In addition, three coherently excited modes at frequencies of 5.6, 3.1 and 2.4 THz are observed. An estimate of the electron-phonon coupling parameter reveals lambda < 0.5, suggesting a limited importance of e-ph coupling to superconductivity in Fe pnictides.



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