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Quantitative Study on Current-Induced Effect in an Antiferromagnet Insulator/Pt Bilayer Film

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 نشر من قبل Pengxiang Zhang
 تاريخ النشر 2019
  مجال البحث فيزياء
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Quantitative investigation on the current-induced torque in antiferromagnets represents a great challenge, due to the lack of an independent method for controlling Neel vectors. Here by utilizing an antiferromagnetic insulator with Dzyaloshinskii-Moriya interaction, {alpha}-Fe2O3, we show that the Neel vector can be controlled with a moderate external field, which is further utilized to calibrate the current-induced magnetic dynamics. We find that the current-induced magnetoresistance change in antiferromagnets can be complicated by resistive switching that does not have a magnetic origin. By excluding non-magnetic switching and comparing the current-induced dynamics with the field-induced one, we determine the nature and magnitude of current-induced effects in Pt/{alpha}-Fe2O3 bilayer films.



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