First-principles calculations to investigate physical properties of oxide perovskites LaBO3 (BMn, Fe) for thermo-spintronic devices

Oxide perovskite LaBO3 was extensively examined using first principles computations with density functional theory. Various exchange-correlation functionals were applied to investigate several of its physical properties. The compound's stability was validated through energy optimization in both ferromagnetic and non-magnetic phases, revealing that the ferromagnetic phase is more energetically stable. With the optimized lattice parameter, we explored various electronic, mechanical, magnetic, and thermodynamic properties. According to the GGA + U approximation, LaMnO3 and LaFeO3 exhibit half-metallic and semiconductor characteristics, respectively. The elastic constants, along with the elastic moduli (Y, B, and G) and Vickers hardness (Hv) number, were calculated to assess the mechanical properties of both compounds. Our simulation confirmed the ductile nature of the material by analyzing the Cauchy pressure, Poisson's ratio, and Pugh ratio. Additionally, thermodynamic parameters, including thermal expansion, specific heat capacity, and Debye temperature, were computed using the quasi-harmonic Debye model. The study's findings suggest that these materials are suitable for thermo-spintronic devices. •First-principles computations: Oxide perovskite LaBO3 was analyzed using density functional theory (DFT).•Exchange-correlation functionals: Various functionals were applied to study physical properties.•Stability: Energy optimization validated stability in both ferromagnetic (FM) and non-magnetic (NM) phases, with FM phase being more stable.•Lattice parameter: Optimization led to exploration of electronic, mechanical, magnetic, and thermodynamic properties.•GGA + U approximation: Revealed LaMnO3 as half-metallic and LaFeO3 as a semiconductor.•Mechanical properties: Elastic constants, moduli (Y, B, G), and Vickers hardness (Hv) were calculated.•Ductility: Confirmed via Cauchy pressure, Poisson's ratio, and Pugh ratio analysis.