Role of spin-orbit coupling in spin-spiral structures in Fe monolayer on W(110): A first-principles noncollinear magnetism study

The stability of spin-spiral structures in an Fe monolayer on a W(110) substrate is investigated by means of the first-principles film full-potential linearized augmented plane-wave method, and the role of spin-orbit coupling (SOC) on the spin-spiral structures is determined. Our calculations demonstrate that without SOC, the spin-spiral structures are energetically favored over the ferromagnetic (FM) state, but that when the strong SOC at the Fe/W(110) interface is introduced, the formation of the spin-spiral structures is suppressed. Thus, the ground state of the system appears to be the FM state-as observed in experiments. (C) 2009 American Institute of Physics. [DOI: 10.1063/1.3070635]