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Efficient spin torques in antiferromagnetic CoO/Pt quantified by comparing field- and current- induced switching

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 نشر من قبل Lorenzo Baldrati
 تاريخ النشر 2020
  مجال البحث فيزياء
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We achieve current-induced switching in collinear insulating antiferromagnetic CoO/Pt, with fourfold in-plane magnetic anisotropy. This is measured electrically by spin Hall magnetoresistance and confirmed by the magnetic field-induced spin-flop transition of the CoO layer. By applying current pulses and magnetic fields, we quantify the efficiency of the acting current-induced torques and estimate a current-field equivalence ratio of $4x10^{-11} T A^{-1} m^2$. The Neel vector final state ($n perp j$) is in line with a thermomagnetoelastic switching mechanism for a negative magnetoelastic constant of the CoO.

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