First-principles study of Dzyaloshinskii-Moriya Interaction

AdAbstract: The Dzyaloshinskii-Moriya Interaction (DMI) between spins induced by spin-orbit coupling (SOC) in magnetic materials lacking inversion symmetry and in particular at the interface between ferromagnetic (FM) and heavy nonmagnetic (NM) metals plays prominent and essential role for creating topologically non-trivial textures called magnetic skyrmions and for fast domain wall (DW) dynamics driven by spin-orbit torques. Thus, much attention has been paid on searching efficient material combinations giving rise to large DMI values at FM/NM interfaces The study of DMI at Pt/Co interfaces [1] has unveiled the features that the large anticlockwise (ACW) DMI of the bilayers has a predominant contribution from pair couplings between the spins of the interfacial Co layer. This DMI between the interface Co spins is directly related to the change of the SOC energy in the interface Pt atoms, which demonstrating the picture of Fert-Levy type interfacial DMI from first-principles. Based on the above study, we propose several approaches to control the DMI in ultrathin magnetic films and enhance its amplitude. [2]Moreover, we explore the possibility of electric field control of DMI in FM/NM/Oxide structures, which opens a route towards an efficient way for controlling skyrmions. [3] Finally, we report the Rashba effect induced interfacial Dzyaloshinskii-Moriya Interaction (DMI) at graphene /FM interfaces [4].