|DATE||December 07 (Fri), 2018|
|INSTITUTE||Max Planck POSTECH/Korea Research Initiative|
|TITLE||Topological ferromagnetic van der Waals material Fe3GeTe2 with large anomalous Hall current|
We studied Ferromagnetism van der Waals material Fe3GeTe2 with Tc~220K exhibiting large anomalous Hall current. With the help of theoretical methods such as density functional theory and group theory, we have found that the large anomalous Hall current in Fe3GeTe2 has topological origin. In the absence of spin-orbit coupling, there are nodal lines in K and K’ points for a single spin channel near Fermi level. Theoretical analyses reveral interlayer hybridization of Fe orbitals in Fe3GeTe2 is responsible for these nodal-lines. With spin-orbit coupling, large Berry curvatures from the anti-crossings of nodal-line oriented bands result in the large anomalous Hall current. We also take into account the effect of Fe correlation utilizing dynamical mean field theory, and Fe vacancy effect using coherent potential approximation, which demonstrate the stability of this phenomenon. The comparison of theoretical and experimental results shows good agreements. Fe3GeTe2 might be a good platform for the research of 2-dimensional topological ferromagnetic materials.