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Heat-induced damping modification in YIG/Pt hetero-structures

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 نشر من قبل Matthias Benjamin Jungfleisch
 تاريخ النشر 2012
  مجال البحث فيزياء
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We experimentally demonstrate the manipulation of magnetization relaxation utilizing a temperature difference across the thickness of an yttrium iron garnet/platinum (YIG/Pt) hetero-structure: the damping is either increased or decreased depending on the sign of the temperature gradient. This effect might be explained by a thermally-induced spin torque on the magnetization precession. The heat-induced variation of the damping is detected by microwave techniques as well as by a DC voltage caused by spin pumping into the adjacent Pt layer and the subsequent conversion into a charge current by the inverse spin Hall effect.



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