Beyond conventional storage: DFT and Monte Carlo investigation of low-temperature half-metallic perovskites for next-generation spintronics

We present a comprehensive theoretical investigation of the structural, electronic, optical, and magnetic properties of $CsSr{O}_3$ and $RbSr{O}_3$ perovskites using first-principles density functional theory (DFT) calculations combined with Monte Carlo simulations. Our findings reveal that both compounds exhibit remarkable half-metallic ferromagnetic behavior, with $CsSr{O}_3$ displaying spin-polarized band gaps of 9.558 eV and 0 eV for spin-up and spin-down channels, respectively, while $RbSr{O}_3$ shows corresponding gaps of 9.982 eV and 0 eV. The phonon dispersion calculations and formation energy values confirm both dynamic and thermodynamic stability of these structures. Monte Carlo simulations predict Curie temperatures of 75.3 K for $CsSr{O}_3$ and 60 K for $RbSr{O}_3$, indicating robust ferromagnetic ordering at low temperatures. Although these transition temperatures fall below room temperature, the coexistence of half-metallicity and ferromagnetism in these perovskite compounds is intriguing for low-temperature spintronic applications.