Orientation-dependent current-induced motion of skyrmions with various topologies

We study the current-driven motion of metastable localized spin structures with various topological charges in a $({\mathrm{Pt}}_{0.95}{\mathrm{Ir}}_{0.05})$/Fe bilayer on a Pd(111) surface by combining atomistic spin model simulations with an approach based on the generalized Thiele equation. We demonstrate that besides a distinct dependence on the topological charge itself the dynamic response of skyrmionic structures with topological charges $Q=\ensuremath{-}1$ and $Q=3$ to a spin-polarized current exhibits an orientation dependence. We further show that such an orientation dependence can be induced by applying an in-plane external field, possibly opening up a different pathway to the manipulation of skyrmion dynamics.