Ab-initio investigation of electronic and magnetic properties of Heusler alloys

A full-potential linearized augmented-plane-wave method (FLAPW) is used to investigate the electronic structure of several bulk ferromagnetic Heusler alloys as well as Ni2MnGa(0 0 1) thin film and it on the GaAs(0 0 1) substrate. The changes of electronic structure and magnetic properties at surface are analyzed. The electronic structure at a (0 0 1) surface shows differences compared to the bulk. We find the increase of the magnetic moment at surface Mn atoms by about 0.3μB whereas Ni atoms have ∼0.3–0.4μB in the surface and subsurface layers.