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Distinct domain-wall motion between creep and flow regimes near the angular momentum compensation temperature of ferrimagnet

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 نشر من قبل Kab-Jin Kim
 تاريخ النشر 2017
  مجال البحث فيزياء
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We investigate a magnetic domain-wall (DW) motion in two dynamic regimes, creep and flow regimes, near the angular momentum compensation temperature (T_A) of ferrimagnet. In the flow regime, the DW speed shows sharp increase at T_A due to the emergence of antiferromagnetic DW dynamics. In the creep regime, however, the DW speed exhibits a monotonic increase with increasing the temperature. This result suggests that, in the creep regime, the thermal activation process governs the DW dynamics even near T_A. Our result unambiguously shows the distinct behavior of ferrimagnetic DW motion depending on the dynamic regime, which is important for emerging ferrimagnet-based spintronic applications.

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