First-principles prediction of half metallic-ferromagnetism in La0.25Sr0.75Sn0.4In0.25Ru0.35O3 and enhanced experimental electrical and magnetic behaviours

Abstract

A successful mechanochemical synthesis of a new nanoscale semi-conductive perovskite, La_0.25Sr_0.75Sn_0.4In_0.25Ru_0.35O₃ (LSSIRuO) was achieved through co-doping of SrSnO₃. XRD and IR analyses confirmed that the sample crystallized in a pure perovskite GdFeO₃ type structure (Pnma space group). Diffuse reflectance measurements revealed a direct band gap of 1.3 eV, which was significantly narrowed compared to that of SrSnO₃ (4.1 eV). The investigation of DFT calculations into the sextenary systems La_0.25Sr_0.75[Sn_0.4Ru_0.35]In_0.25O₃ and La_0.25Sr_0.75[Sn_0.5Ru_0.25]In_0.25O₃ has revealed semiconductor behavior, very close to a semiconductor–semi metal transition. Importantly, Arrhenius-type charge transport was confirmed through a temperature-dependent conductivity study of the sample, showing good electrical conductivity of 3.6 S m⁻¹ at 513 K with an activation energy of E_a = 0.19 eV. Furthermore, the compound exhibited ferromagnetic ordering at temperatures lower than 155 K, contrasting the diamagnetic behavior of SrSnO₃. The narrower band gap value (1.3 eV) and improved electrical properties of LSSIRuO, in addition to its ferromagnetic characteristics, distinguish it as a promising candidate for applications in optoelectronics, as well as in memory and spintronic devices.