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Scaling the electrical current switching of exchange bias in fully-epitaxial antiferromagnet/ferromagnet bilayers

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 نشر من قبل Tetsuya Hajiri
 تاريخ النشر 2020
  مجال البحث فيزياء
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While the electrical current manipulation of antiferromagnets (AFMs) has been demonstrated, the extent of the studied AFM materials has been limited with few systematic experiments and a poor understanding. We compare the electrical current switching of the exchange-bias field ($H_{ex}$) in AFM-Mn$_3A$N/ferromagnet-Co$_3$FeN bilayers. An applied pulse current can manipulate $H_{ex}$ with respect to the current density and FM layer magnetization, which shifts exponentially as a function of the current density. We found that the saturation current density and exponential decay constant $tau$ increase with the local moment of AFM Mn atoms. Our results highlight the effect of the AFM local moment to electrical current switching of $H_{ex}$, although it has a near-zero net magnetization, and may provide a facile way to explore the electrical current manipulation of AFM materials.

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