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Half-metallic ferromagnets for magnetic tunnel junctions

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 نشر من قبل Ph. Mavropoulos
 تاريخ النشر 2005
  مجال البحث فيزياء
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Using theoretical arguments, we show that, in order to exploit half-metallic ferromagnets in tunneling magnetoresistance (TMR) junctions, it is crucial to eliminate interface states at the Fermi level within the half-metallic gap; contrary to this, no such problem arises in giant magnetoresistance elements. Moreover, based on an a priori understanding of the electronic structure, we propose an antiferromagnetically coupled TMR element, in which interface states are eliminated, as a paradigm of materials design from first principles. Our conclusions are supported by ab-initio calculations.



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