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Basic obstacle for electrical spin-injection from a ferromagnetic metal into a diffusive semiconductor

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 نشر من قبل Georg Schmidt
 تاريخ النشر 1999
  مجال البحث فيزياء
والبحث باللغة English
 تأليف G. Schmidt




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We have calculated the spin-polarization effects of a current in a two dimensional electron gas which is contacted by two ferromagnetic metals. In the purely diffusive regime, the current may indeed be spin-polarized. However, for a typical device geometry the degree of spin-polarization of the current is limited to less than 0.1%, only. The change in device resistance for parallel and antiparallel magnetization of the contacts is up to quadratically smaller, and will thus be difficult to detect.



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