Non‐collinear chiral antiferromagnets like Mn3Sn and Mn3Ge are known to show gigantic anomalous Hall response depending on the orientation of their inverse chiral magnetic order of Mn atoms in Kagomé layers. Here we study the stability of such magnetic order in the absence of external magnetic fields on the basis of stochastic Landau–Lifshitz–Gilbert equation for a simplified two‐dimensional model of these materials. We find that even without external magnetic fields, the ordered state is, once formed, highly stable against thermal fluctuations. Moreover, we show that if Mn spins are well confined inside each Kagomé layers, by injecting spin‐current using spin‐filtering effect of ferromagnetic metals, we can control the in‐plane magnetic structure of non‐collinear chiral antiferromagnets in a field free way.
Non‐collinear antiferromagnets (AFMs) are an exciting new platform for studying intrinsic spin Hall effects (SHEs), phenomena that arise from the materials’ band structure, Berry phase curvature, and linear response to an external electric field. In contrast to conventional SHE materials, symmetry analysis of non‐collinear antiferromagnets does not forbid non‐zero longitudinal and out‐of‐plane spin currents with polarization and predicts an anisotropy with current orientation to the magnetic lattice. Here, multi‐component out‐of‐plane spin Hall conductivities are reported in L12‐ordered antiferromagnetic PtMn3thin films that are uniquely generated in the non‐collinear state. The maximum spin torque efficiencies (
- NSF-PAR ID:
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Materials
- Medium: X
- Sponsoring Org:
- National Science Foundation
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