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Magnetization dependent current rectification in (Ga,Mn)As magnetic tunnel junctions

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 نشر من قبل Shingo Katsumoto
 تاريخ النشر 2011
  مجال البحث فيزياء
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We have found that the current rectification effect in triple layer (double barrier) (Ga,Mn)As magnetic tunnel junctions strongly depends on the magnetization alignment. The direction as well as the amplitude of the rectification changes with the alignment, which can be switched by bi-directional spin-injection with very small threshold currents. A possible origin of the rectification is energy dependence of the density of states around the Fermi level. Tunneling density of states in (Ga,Mn)As shows characteristic dip around zero-bias indicating formation of correlation gap, the asymmetry of which would be a potential source of the energy dependent density of states.



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