Synthesis and properties of stoichiometric Mn3-xFexSn thin films

We synthesized and characterized stacked Kagome thin films of the type Mn3-xFexSn (x = 0, 1, 2), motivated by the search for new spintronic materials with high perpendicular magnetic anisotropy (PMA) and tunable magnetic properties that are recognized to be useful for the magnetic random access memory technology. All samples exhibited a polycrystalline hexagonal structure and bulk-like characteristics. X-ray diffraction data strongly suggest that Fe doping leads to significant anti-site disorder. We demonstrate that Fe substitution for Mn leads to highly tunable magnetic properties from a low magnetization non-collinear magnetic structure in Mn3Sn to a high magnetization predominantly collinear magnetic structure for Fe2MnSn via a complex magnetic configuration for Mn2FeSn, which contains coexisting ferromagnetic and antiferromagnetic phases with a strong exchange bias effect. Temperature dependent resistivity measurements revealed a non-metallic behavior in Mn2FeSn, which we attribute to the competing magnetic interactions within the material. In contrast, Fe2MnSn exhibits a metallic behavior, a high Curie temperature of 512 K, a positive anisotropic magnetoresistance response, and a strong magneto-optical Kerr effect.