Emergence of spin spiral magnetic order in Mn based inverse Heusler alloys

In this article we demonstrate, by first principles density functional calculations, the emergence of spin-spiral magnetic order in Mn₂NiX(X=Al,Ga,In,Sn) inverse Heusler alloys with the application of pressure. This noncollinearity originates from the features in the band structures and the nesting of fermi surfaces of collinear spin bands. The calculated interatomic magnetic exchange parameters suggest that the frustrations in the Mn sublattice with octahedral symmetry are responsible for the stabilization of a noncollinear state. We propose that the pressure induced stabilization of spin-spiral magnetic order is a general feature of magnetic alloys crystallizing in inverse Heusler structures.