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Chemical potential of quasi-equilibrium magnon gas driven by pure spin current

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 نشر من قبل Vladislav Demidov
 تاريخ النشر 2017
  مجال البحث فيزياء
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We show experimentally that the spin current generated by the spin Hall effect drives the magnon gas in a ferromagnet into a quasi-equilibrium state that can be described by the Bose-Einstein statistics. The magnon population function is characterized either by an increased effective chemical potential or by a reduced effective temperature, depending on the spin current polarization. In the former case, the chemical potential can closely approach, at large driving currents, the lowest-energy magnon state, indicating the possibility of spin current-driven Bose-Einstein condensation.



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