Electron correlation effects in the half-metallic NiMnSb within a cluster-perturbation approach with ab-initio parameters

Abstract

Using a combination of electronic-structure and many-body calculations, we investigate correlations effects in the halfmetallic ferromagnet NiMnSb. A realistic many-body Hamiltonian, containing only Mn-d orbitals shows the importance of non-quasiparticle states just above the Fermi level. Our results suggest that for a better description of low energy states around Fermi level, Ni-d orbitals should be explicitly included.

Keywords

• half metal
• cluster perturbation
• electron correlation