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Inhomogeneous Gilbert damping from impurities and electron-electron interactions

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 نشر من قبل Ewelina Hankiewicz
 تاريخ النشر 2008
  مجال البحث فيزياء
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We present a unified theory of magnetic damping in itinerant electron ferromagnets at order $q^2$ including electron-electron interactions and disorder scattering. We show that the Gilbert damping coefficient can be expressed in terms of the spin conductivity, leading to a Matthiessen-type formula in which disorder and interaction contributions are additive. In a weak ferromagnet regime, electron-electron interactions lead to a strong enhancement of the Gilbert damping.



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