Accurate scheme to calculate the interatomic Dzyaloshinskii-Moriya interaction parameters

An accurate scheme to calculate the interatomic Dzyaloshinskii-Moriya interaction (DMI) parameters is presented, which is based on the fully relativistic Korringa-Kohn-Rostoker Green function (KKR-GF) technique. Corresponding numerical results are compared with those obtained using other schemes reported in the literature. The differences found can be attributed primarily to the different reference states used in the various approaches. The advantage of the present approach is that the DMI vectors can in a natural way be connected with the DMI-related torques on local magnetic moments. In addition an expression for the DMI parameters formulated for a micromagnetic model Hamiltonian is presented that provides a connection to the DMI parameters calculated for atomistic Hamiltonians. This formulation also allows the discussion of the DMI in terms of specific features of the electronic band structure.