Influence of order on the magnetic and electronic properties of quaternary half-metallic Heusler CoFeTiSn alloy

The crystal structure, magnetic and electronic properties and influence of order on half-metallicity of a quaternary Heusler CoFeTiSn alloy were studied. We found that CoFeTiSn alloy crystallizes to a LiMgPdSn prototype structure (space group F-43 m, No. 216). The relationship between the magnetic moments (Mt = 1 μB) and the number of valence electrons (NV= 25) obeys the Slater-Pauling rule Mt = NV - 24. The electronic structure shows half-metallic property. Anti-site disorder between magnetic atoms Fe (or Co) and non-magnetic atoms Ti (or Sn), i.e. Co1-xTix, Co1-xSnx, Fe1-xTix and Fe1-xSnx has a significant influence on the magnetic and electronic properties of the alloys and is harmful to the half-metallic property. Anti-site disorder could be effectively depressed under ordering treatment. These results indicate CoFeTiSn is a potential half-metallic ferromagnet and promising for spintronic applications. •Confirm the LiMgPdSn structure and atomic arrangement of CoFeTiSn.•Predict the half-metallicity for CoFeTiSn.•Reveal the influence of anti-site disorder on half-metallicity.