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Sizable spin-transfer torque in Bi/Ni80Fe20 bilayer film

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 نشر من قبل Masashi Shiraishi
 تاريخ النشر 2020
  مجال البحث فيزياء
والبحث باللغة English
 تأليف M. Matsushima




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The search for efficient spin conversion in Bi has attracted great attention in spin-orbitronics. In the present work, we employ spin-torque ferromagnetic resonance to investigate spin conversion in Bi/Ni80Fe20(Py) bilayer films with continuously varying Bi thickness. In contrast with previous studies, sizable spin-transfer torque (i.e., a sizable spin-conversion effect) is observed in Bi/Py bilayer film. Considering the absence of spin conversion in Bi/yttrium-iron-garnet bilayers and the enhancement of spin conversion in Bi-doped Cu, the present results indicate the importance of material combinations to generate substantial spin-conversion effects in Bi.



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