关键词: non-collinear antiferromagnets, anomalous Hall effect, magnetization switching, spin-orbit torque

Abstract: Topological magnetotransport in non-collinear antiferromagnets has attracted extensive attention due to the exotic phenomena such as large anomalous Hall effect (AHE), magnetic spin Hall effect, and chiral anomaly. The materials exhibiting topological antiferromagnetic physics are typically limited in special Mn$_{3}X$ family such as Mn$_{3}$Sn and Mn$_{3}$Ge. Exploring the topological magnetotransport in common antiferromagnetic materials widely used in spintronics will not only enrich the platforms for investigating the non-collinear antiferromagnetic physics, but also have great importance for driving the nontrivial topological properties towards practical applications. Here, we report remarkable AHE, anisotropic and negative parallel magnetoresistance in the magnetron-sputtered Ir$_{20}$Mn$_{80}$ antiferromagnet, which is one of the most widely used antiferromagnetic materials in industrial spintronics. The ab initio calculations suggest that the Ir$_{4}$Mn$_{16}$ (IrMn$_{4}$) or Mn$_{3}$Ir nanocrystals hold nontrivial electronic band structures, which may contribute to the observed intriguing magnetotransport properties in the Ir$_{20}$Mn$_{80}$. Further, we demonstrate the spin-orbit torque switching of the antiferromagnetic Ir$_{20}$Mn$_{80}$ by the spin Hall current of Pt. The presented results highlight a great potential of the magnetron-sputtered Ir$_{20}$Mn$_{80}$ film for exploring the topological antiferromagnet-based physics and spintronics applications.

Key words: non-collinear antiferromagnets, anomalous Hall effect, magnetization switching, spin-orbit torque