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Relativistic Neel-order fields induced by electrical current in antiferromagnets

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 نشر من قبل Tomas Jungwirth
 تاريخ النشر 2014
  مجال البحث فيزياء
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We predict that a lateral electrical current in antiferromagnets can induce non-equilibrium Neel order fields, i.e. fields whose sign alternates between the spin sublattices, which can trigger ultra-fast spin-axis reorientation. Based on microscopic transport theory calculations we identify staggered current-induced fields analogous to the intra-band and to the intrinsic inter-band spin-orbit fields previously reported in ferromagnets with a broken inversion-symmetry crystal. To illustrate their rich physics and utility, we considered bulk Mn2Au with the two spin sublattices forming inversion partners, and a 2D square-lattice antiferromagnet with broken structural inversion symmetry modelled by a Rashba spin-orbit coupling. We propose an AFM memory device with electrical writing and reading.


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