Edge non-collinear magnetism in nanoribbons of Fe3GeTe2 and Fe3GaTe2

Abstract: Fe3GeTe2 and Fe3GaTe2 are ferromagnetic conducting materials of van der Waals-type with unique magnetic properties that are highly promising for the development of new spintronic, orbitronic and magnonic devices. Even in the form of two-dimensional-like ultrathin films, they exhibit relatively high Curie temperature, magnetic anisotropy perpendicular to the atomic planes and multiple types of Hall effects. We explore nanoribbons made from single layers of these materials and show that they display non-collinear magnetic ordering at their edges. This magnetic inhomogeneity allows angular momentum currents to generate magnetic torques at the sample edges, regardless of their polarization direction, significantly enhancing the effectiveness of magnetization manipulation in these systems. We also demonstrate that it is possible to rapidly reverse the magnetization direction of these nanostructures by means of spin-orbit and spin-transfer torques with rather low current densities, making them quite propitious for non-volatile magnetic memory units.