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Evidence for the Presence of Spin Accumulation in Localized States at Ferromagnet-Silicon Interfaces

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 نشر من قبل Kohei Hamaya
 تاريخ النشر 2012
  مجال البحث فيزياء
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We experimentally show evidence for the presence of spin accumulation in localized states at ferromagnet-silicon interfaces, detected by electrical Hanle effect measurements in CoFe/$n^{+}$-Si/$n$-Si lateral devices. By controlling the measurement temperature, we can clearly observe marked changes in the spin-accumulation signals at low temperatures, at which the electron transport across the interface changes from the direct tunneling to the two-step one via the localized states. We discuss in detail the difference in the spin accumulation between in the Si channel and in the localized states.



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