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Temperature dependence of spin-orbit torque effective fields in the diluted magnetic semiconductor (Ga,Mn)As

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 نشر من قبل Kevin Edmonds
 تاريخ النشر 2014
  مجال البحث فيزياء
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We report on a study of the temperature-dependence of current-induced effective magnetic fields due to spin-orbit interactions in the diluted ferromagnetic semiconductor (Ga,Mn)As. Contributions from the effective fields as well as from the anomalous Nernst effect are evident in the difference between transverse resistance measurements as a function of an external magnetic field for opposite orientations of the applied current. We separately extract these contributions by fitting to a model of coherently rotating magnetization. The component of the effective field with Dresselhaus symmetry is substantially enhanced with increasing temperature, while no significant temperature-dependence is observed for the component with Rashba symmetry.



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