Inducing magnetism in non-magnetic alpha-FeSi2 by distortions and/or intercalations

By means of hybrid ab initio + model approach we show that the lattice distortions in non-magnetic α-FeSi₂ can induce a magnetic state. However, we find that the distortions required for the appearance of magnetism in non-magnetic α-FeSi₂ are too large to be achieved by experimental fabrication of thin films. For this reason we suggest a novel way to introduce magnetism in α-FeSi₂ using “chemical pressure” that is, intercalating the α-FeSi₂ films by light elements. Theoretical study of the distortions resulting from intercalation reveals that the most efficient intercalants for formation of magnetism and a high spin polarization are lithium, phosphorus and oxygen. Investigation of the dependency of the magnetic moments and spin polarisation on the intercalation atoms concentration shows that the spin polarization remains high even at small concentrations of intercalated atoms, which is extremely important for modern silicate technology.