Chiral Spin and Orbital Angular Momentum Textures in Mn Chains on W(110): Interplay of Spin-Orbit Coupling and Crystal Field Effects

Abstract

Stabilization of unusual spin-orbit driven magnetic orderings are achieved for chains of Mn atoms deposited on a W(110) substrate. First-principles electronic structure calculations show that the ground state spin configuration is non-collinear, forming chiral spiral-like structures, driven by competing nearest and next-nearest neighbor interactions. The orbital magnetic moments are also found to exhibit non-collinear ordering that, interestingly, tend to align in-plane for some systems with an orientation distinctly differently from that of the spin moment. We analyse the mechanism behind such behaviour, and find that it is due to the competition between the spin-orbit interaction and crystal-field splitting. Model calculations based on this assumption reproduce the main findings observed in our first-principles calculations.