Ab initio calculation of half-metallicity, magnetic and transport properties of potassium-based KLAO₂ (LA = Ho³⁺, Tm³⁺, Yb³⁺) oxides for spintronics devices

The physical properties of potassium-based KLAO₂ (LA = Ho³⁺, Tm³⁺, Yb³⁺) oxides were examined by the density functional theory (DFT) method under the WIEN2k approximation. The Perdew–Burke–Ernzerhof + generalized gradient approximation (PBE + GGA) method describes the exchange–correlation energy of host materials, which show a hexagonal crystal structure with space group (166_R-3m). The crystal structure of potassium-based lanthanide oxides is energetically stable in ferromagnetic, anti-ferromagnetic, and diamagnetic states. The bandgap and density of states describe the metallic and semiconductor behavior for correlation with spin-up and spin-down channels. The total magnetic moment of host compounds is an integer that describes the half-metallic nature along 100% spin polarization at the Fermi level (E_F). Total and partial magnetic moments of KLAO₂ (LA = Ho³⁺, Tm³⁺, Yb³⁺) occur due to 4f unpaired electronic states that are present. Finally, the BoltzTraP code describes the transport characteristics. The values of Curie temperature are calculated according to the volume optimization curve at room temperature for ferromagnetism. Therefore, potassium-based lanthanide oxides have significant application potential in spintronics devices.