Spin Hall effect in noncollinear kagome antiferromagnets

The spin Hall effect is commonly considered to be related to spin-orbit interaction that causes a deflection of charge carriers according to their spin orientation into opposite directions. Thus, this effect creates spin currents in nonmagnetic materials with spin-orbit coupling. However, recently large spin Hall effects were predicted in coplanar kagome antiferromagnets Mn3X even when spin-orbit interaction is not considered. Therefore, these materials are interesting candidates for spintronic applications. In our theoretical study we reveal two sources that determine the intrinsic spin Hall signal of two-dimensional kagome antiferromagnets. The main contribution to the spin Hall signal is originating from the noncollinear magnetic texture localized on the Mn sites and it is maximal for coplanar systems. In addition to that, spin-orbit coupling or an out-of-plane tilting of the magnetic moments, which are equivalent within the framework of this model, reduce the spin Hall effect effectively