Out-of-plane weak ferromagnetism at room temperature in lattice-distortion non-collinear antiferromagnet of single-crystal Mn₃Sn

Out-of-plane weak ferromagnetic (OWFM) spin arrangements with topological properties can realize a series of interesting physical properties. However, this spin structure tends to exist at low temperatures. The OWFM structure can also be induced at room temperature by hydrostatic pressure, whereas this isotropic approach tends to form helical AFM structures. We report the OWFM spin arrangement in single crystal Mn₃Sn by an anisotropic strategy of high-stressconstrained compression deformation at room temperature. Both experimental and theoretical simulation results show that the alignment of the OWFM spin structure is due to the distortion of the atomic scale caused by the strain energy during deformation. The OWFM spin arrangement can significantly change the magnetic property of Mn₃Sn. As a result, the remanent magnetization M_r for the deformed sample (0.056 μ_B/f.u.) is about eleven times that for the pre-deformed sample (0.005 μ_B/f.u.), and the coercivity (H_c) increases from 0 kOe (pre-deformed sample) to 6.02 kOe (deformed sample). Our findings provide a way to generate the OWFM spin structure at room temperature and may give fresh ideas for creating antiferromagnetic materials with excellent physical properties.