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

Zhandun, Vyacheslav; Zamkova, Natalia; Korzhavyi, Pavel; Sandalov, Igor Source: PHYSICAL CHEMISTRY CHEMICAL PHYSICS, 21 (25):13835-13846; 10.1039/c9cp02361e JUL 7 2019

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.