Field-free, spin-current control of magnetization in non-collinear chiral antiferromagnets

Abstract: 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 Kagome 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 Kagome layers, by injecting spin-current using spin-filtering effect of ferromagnetic metals, we can control the in-plane magnetic structure in a field free way.