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Spin-wave excitations in the SDW state of iron pnictides: a comparison between the roles of interaction parameters

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 نشر من قبل Dheeraj Singh
 تاريخ النشر 2017
  مجال البحث فيزياء
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We investigate the role of Hunds coupling in the spin-wave excitations of the ($pi, 0$) ordered magnetic state within a five-orbital tight-binding model for iron pnictides. To differentiate between the roles of intraorbital Coulomb interaction and Hunds coupling, we focus on the self-consistently obtained mean-field SDW state with a fixed magnetic moment obtained by using different sets of interaction parameters. We find that the Hunds coupling is crucial for the description of various experimentally observed characteristics of the spin-wave excitations including the anisotropy, energy-dependent behavior, and spin-wave spectral weight distribution.



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