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Nonlocal spin torques in Rashba quantum wires with steep magnetic textures

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 نشر من قبل Martin Stier
 تاريخ النشر 2015
  مجال البحث فيزياء
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We provide a general procedure to calculate the current-induced spin-transfer torque which acts on a general steep magnetic texture due to the exchange interaction with an applied spin-polarized current. As an example, we consider a one-dimensional ferromagnetic quantum wire and also include a Rashba spin-orbit interaction. The spin-transfer torque becomes generally spatially non-local. Likewise, the Rashba spin-orbit interaction induces a spatially nonlocal field-like nonequilibrium spin-transfer torque. We also find a spatially varying nonadiabaticity parameter and markedly different domain wall dynamics for very steep textures as compared to wide domain walls.



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