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Electrical control of spin mixing conductance in a Y$_3$Fe$_5$O$_{12}$/Platinum bilayer

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 نشر من قبل Lihui Bai Dr.
 تاريخ النشر 2019
  مجال البحث فيزياء
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We report a tunable spin mixing conductance, up to $pm 22%$, in a Y${}_{3}$Fe${}_{5}$O${}_{12}$/Platinum (YIG/Pt) bilayer.This control is achieved by applying a gate voltage with an ionic gate technique, which exhibits a gate-dependent ferromagnetic resonance line width. Furthermore, we observed a gate-dependent spin pumping and spin Hall angle in the Pt layer, which is also tunable up to $pm$ 13.6%. This work experimentally demonstrates spin current control through spin pumping and a gate voltage in a YIG/Pt bilayer, demonstrating the crucial role of the interfacial charge density for the spin transport properties in magnetic insulator/heavy metal bilayers.



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