Electronic structure and Slater–Pauling behaviour in half-metallic Heusler alloys calculated from first principles

Abstract

Intermetallic Heusler alloys are amongst the most attractive half-metallic\nsystems due to the high Curie temperatures and the structural similarity to the\nbinary semiconductors. In this review we present an overview of the basic\nelectronic and magnetic properties of both Heusler families: the so-called\nhalf-Heusler alloys like NiMnSb and the the full-Heusler alloys like\nCo$_2$MnGe. \\textit{Ab-initio} results suggest that both the electronic and\nmagnetic properties in these compounds are intrinsically related to the\nappearance of the minority-spin gap. The total spin magnetic moment $M_t$\nscales linearly with the number of the valence electrons $Z_t$, such that\n$M_t=Z_t-24$ for the full-Heusler and $M_t=Z_t-18$ for the half-Heusler alloys,\nthus opening the way to engineer new half-metallic alloys with the desired\nmagnetic properties.\n