Superstructural arrangement and half-metallic semiconductor nature of the ferromagnetic material Ca2TiFeO6

The modern technological applicability of materials depends substantially on their structural and physical properties. In the area of spintronics, materials design focuses on attributes such as multiferroicity, colossal magnetoresistance, ferromagnetism in semiconductors and half-metallicity, among others, which are conducive to the development of devices based on spin-polarized currents. For these purposes, the perovskite family has proven useful for spin technologies. In this manuscript, the synthesis of the material Ca2TiFeO6 is reported. Crystallographic analysis reveals that it adopts a monoclinic structure (space group P21/n), classifiable as a double perovskite type due to the ordered distribution of Ti and Fe cations along the crystallographic axes, forming a superstructure. Magnetic response measurements show the ferromagnetic feature and band structure, and density of electronic states calculations suggest the occurrence of half-metallicity. For one of the spin orientations, the material behaves like a metal due to strong hybridizations of the 4d-Fe orbitals with 2p-O, and for the other like a semiconductor with band gap of 2.3 eV, thanks to the availability of 3d-Fe and 3d-Ti states in the conduction band. The results demonstrate the multifunctionality of the material for use in spintronics technology.