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Spin-current injection and detection in strongly correlated organic conductor

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 نشر من قبل Zhiyong Qiu
 تاريخ النشر 2015
  مجال البحث فيزياء
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Spin-current injection into an organic semiconductor $rm{kappatext{-}(BEDTtext{-}TTF)_2Cu[N(CN)_2]Br}$ film induced by the spin pumping from an yttrium iron garnet (YIG) film. When magnetization dynamics in the YIG film is excited by ferromagnetic or spin-wave resonance, a voltage signal was found to appear in the $rm{kappatext{-}(BEDTtext{-}TTF)_2Cu[N(CN)_2]Br}$ film. Magnetic-field-angle dependence measurements indicate that the voltage signal is governed by the inverse spin Hall effect in $rm{kappatext{-}(BEDTtext{-}TTF)_2Cu[N(CN)_2]Br}$. We found that the voltage signal in the $rm{kappatext{-}(BEDTtext{-}TTF)_2Cu[N(CN)_2]Br}$/YIG system is critically suppressed around 80 K, around which magnetic and/or glass transitions occur, implying that the efficiency of the spin-current injection is suppressed by fluctuations which critically enhanced near the transitions.

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