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Spin accumulation in forward-biased MnAs/GaAs Schottky diodes

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 نشر من قبل David D. Awschalom
 تاريخ النشر 2004
  مجال البحث فيزياء
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We describe a new means for electrically creating spin polarization in semiconductors. In contrast to spin injection of electrons by tunneling through a reverse-biased Schottky barrier, we observe spin accumulation at the metal/semiconductor interface of forward-biased ferromagnetic Schottky diodes, which is consistent with a theory of spin-dependent reflection off the interface. Spatiotemporal Kerr microscopy is used to image the electron spin and the resulting dynamic nuclear polarization that arises from the non equilibrium carrier polarization.



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