Electronic structure, optical and magnetic properties of double Perovskites La2MTiO6 (M = Co, Ni, Cu and Zn)

Abstract Structural, electronic, optical and magnetic properties of titanium based perovskites La2MTiO6 (M = Co, Ni, Cu and Zn) are investigated in monoclinic phase with space group (P21/n) in the domain of density functional theory (DFT). The generalized gradient approximation plus Hubbard potential (GGA + U) is utilized to study these high correlated electrons systems. Structural parameters are found in closed agreement with experiments. Cohesive energy reveals that La2CoTiO6 is more stable among these compounds. The electronic properties show the semiconductor behavior of these compounds with band gap varies from 1.02 to 2.3 eV. Optical properties demonstrate that all these compounds are potential candidates for optoelectronic devices. The electrical resistivity which increases in a sequence from Co to Zn also confirms the semiconductor nature of these compounds. The magnetic susceptibility curves show that La2CoTiO6, La2NiTiO6 and La2CuTiO6 are antiferromagnetic whereas La2ZnTiO6 is a paramagnetic material. Based on the semiconductor antiferromagnetic nature of La2CoTiO6, La2NiTiO6 and La2CuTiO6 it is expected that these compounds could be used as pinning layers in spin valves and storage devices.