Comparative study of tight-binding and ab initio electronic structure calculations focused on magnetic anisotropy in ordered CoPt alloy

Abstract

An empirical multiorbital (spd) tight binding (TB) model including magnetism and spin-orbit coupling is applied to calculations of magnetic anisotropy energy (MAE) in CoPt L10 structure. A realistic Slater-Koster parametrisation for single-element transition metals is adapted for the ordered binary alloy. Spin magnetic moment and density of states are calculated using a full-potential linearized augmented plane-wave (LAPW) ab initio method and our TB code with different variants of the interatomic parameters. Detailed mutual comparison of this data allows for determination of a subset of the compound TB parameters tuning of which improves the agreement of the TB and LAPW results. MAE calculated as a function of band filling using the refined parameters is in broad agreement with ab initio data for all valence states and in quantitative agreement with ab initio and experimental data for the natural band filling. Our work provides a practical basis for further studies of relativistic magnetotransport anisotropies by means of local Green's function formalism which is directly compatible with our TB approach.

Intersublattice magnetocrystalline anisotropy using a realistic tight-binding method based on maximally localized Wannier functions

“…Correspondingly, the MAE also improves as we discuss later. In comparison to a previously reported empirical TB method [40] that used Slater-Koster parametrization, our TB method shows significantly better agreement with DFT.…”

Relativistic Néel-Order Fields Induced by Electrical Current in Antiferromagnets

“…The form of the tight-binding Hamiltonian was obtained following the procedure for bimetallic alloys described in Ref. [33]. The accuracy of the tight-binding energy spectrum is confirmed in Fig.…”

Interface-Generated Spin Currents

“…The materials are composed of either Co, Cu, or Pt atoms. We use a tight-binding model fitted to first principles calculations to simulate the material systems [26] [27] and Green's functions techniques to obtain the electronic wavefunctions, spin currents, and spin torques in the sample [28,29] [30].…”