Spin polarization tuning in Mn$_{X}$Fe$_{1-X}$Ge$_{3}$

Experimentally, the intermetallic compound Mn4FeGe3 has been recently shown to exhibit enhanced magnetic properties and spin polarization compared to the Mn5Ge3 parent compound. The present ab initio study focuses on the effect of Fe substitution on the electronic and magnetic properties of the compound. Our calculations reveal that the changes on the Fermi surface of the doped compound are remarkable, and provide explanations for the enhanced spin polarization observed. Finally, we show that it is indeed possible to tune the degree of spin polarization upon Fe doping, thus making the Mn5−xFexGe3 intermetallic alloy very promising for future spintronic applications.