First-principles studies on physical properties for new half-metallic perovskites AFeO3 (A = Ca, Sr, Ba): Spintronics and energy harvesting applications

Abstract

In this manuscript, structural, electronic, magnetic, and thermoelectric aspects of AFeO₃ (A = Ca, Sr, Ba) have been calculated by means of the Full-Potential Linearized Augmented Plane Wave Method (FP-LAPW) using spin-polarized Density Functional Theory (DFT). The calculated structural parameters have been found to be in good resemblance with previously available work. Enthalpy of formation and cohesive energy along with tolerance factor confirms structural stability. Electronic properties by Trans Blaha modified Becke–Johnson potential (TB-mBJ) suggest metallic behavior in the spin-up channel and semi-conducting behavior in the spin-down channel that supports half-metallic behavior with mixed covalent and ionic bonding. Density of States (DOS) analysis confirms the major contribution of Fe-3d-states in the conduction band and O-2p states in the valence band. The half-metallic nature is further confirmed by the integer value of the total magnetic moment. The real and imaginary parts of dielectric functions, optical conductivities, absorption coefficients, reflectivity, and energy loss function have been calculated to evaluate suitability for optical applications. Thermoelectric properties with temperature range 300–900 K against chemical potential including figure of merit, Seebeck coefficient, thermal conductivities, and power factor, were examined using BoltzTraP code. Findings suggest that AFeO₃ (A = Ca, Sr, Ba) compounds suitable for spintronic, thermoelectric as well as energy harvesting applications.