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Enhanced triplet Andreev reflection off a domain wall in a lateral geometry

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 نشر من قبل Joern Kupferschmidt N
 تاريخ النشر 2009
  مجال البحث فيزياء
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We find that the triplet Andreev reflection amplitude at the interface between a half-metal and an s-wave superconductor in the presence of a domain wall is significantly enhanced if the half metal is a thin film, rather than an extended magnet. The enhancement is by a factor $l_{rm d}/d$, where $l_{rm d}$ is the width of the domain wall and $d$ the film thickness. We conclude that in a lateral geometry, domain walls can be an effective source of the triplet proximity effect.

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