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Voltage controlled spin injection in a (Ga,Mn)As/(Al,Ga)As Zener diode

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 نشر من قبل Pol van Dorpe
 تاريخ النشر 2005
  مجال البحث فيزياء
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The spin polarization of the electron current in a p-(Ga,Mn)As-n-(Al,Ga)As-Zener tunnel diode, which is embedded in a light-emitting diode, has been studied theoretically. A series of self-consistent simulations determines the charge distribution, the band bending, and the current-voltage characteristics for the entire structure. An empirical tight-binding model, together with the Landauer- Buttiker theory of coherent transport has been developed to study the current spin polarization. This dual approach allows to explain the experimentally observed high magnitude and strong bias dependence of the current spin polarization.



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