Magnetic spin Hall effect in non-collinear antiferromagnet Mn3Sn

Kouta Kondou

Spin Hall effect (SHE) provides the spin-charge interconversion in non-magnetic materials, which has drawn much attention because of its potential application for efficient magnetization switching via the spin torque [1].
Here we focus on the topological antiferromagnet Mn3Sn to realize the new functionality in spin-charge conversion. Mn3Sn exhibits the large anomalous Hall effect comparable with ferromagnet at room temperature [2]. Figure 1 shows a devise structure for spin accumulation detection. By applying the charge current on a Mn3Sn strip, spin accumulation can be detected electrically by the ferromagnetic electrode. This technique enables us to observe the SHE in Mn3Sn, exhibiting a sign change when its small magnetic moment switches orientation. Additionally, we succeeded in observation of the sign change in the inverse effect by means of spin pumping method [3]. These new SHEs were named Magnetic spin Hall effect (MSHE) and Magnetic inverse spin Hall effect (MISHE). Recently we fabricated the ferromagnetic layer/Mn3Sn bilayer to investigate the spin torque due to MSHE in Mn3Sn, which can be expected to realize the unconventional spin torque generation.

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[2] S. Nakatsuji, N. Kiyohara and T. Higo, Nature 527, 212 (2015).
[3] M. Kimata, H. Chen, K. Kondou et al., Nature 565, 627 (2019).