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Large Anomalous Hall Effect in Topological Insulators Proximitized by Collinear Antiferromagnets

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 نشر من قبل Chao Lei
 تاريخ النشر 2021
  مجال البحث فيزياء
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CrSb is an attractive material for room-temperature antiferromagnetic spintronic applications because of its high N{e}el temperature $sim$700 K and semi-metallic character. We study the magnetic properties of CrSb bilayers on few-layer topological insulator thin films using emph{ab initio} density functional theory. We find that the intrinsic parts of the total anomalous Hall conductivities of the thin films are non-zero, and approximately quantized. The N{e}el temperature of CrSb bilayers on few-layer topological insulator thin films is found to be approximately two times larger than that of an isolated CrSb thin film. Due to the low Fermi level density of states of CrSb, Hall quantization might be achievable by introducing disorder. CrSb bilayers on topological insulator surfaces are therefore attractive candidates for high-temperature quantum anomalous Hall effects.



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