Ferromagnetic half-metallicity of the cubic NaMgO perovskite: from bulk to (001) surfaces.

Exploration of new half-metallic materials for spintronic applications has drawn great attention from researchers. In this work, we investigate the structural, electronic, and magnetic properties of the NaMgO perovskite in the bulk and (001) surface conformations. The results show the half-metallic nature of bulk NaMgO generated by insulator spin-up channels with a large band gap of 6.08 eV and metallic spin-down channels. A total magnetic moment of 3 () is obtained, which is produced mainly by O atoms with a local magnetic moment of 0.94 (). Once the bulk is cleaved along the (001) direction, atomic relaxation takes place to reach an equilibrium, where all constituent atoms exhibit an inward movement. Interestingly, the half-metallicity is retained from the bulk to the (001) surface conformation. The effects of slab termination and thickness on the surface energy, stability, band edges, spin-up energy gaps, and magnetic anisotropy will be also analyzed in detail. The results presented herein introduce the NaMgO perovskite as a promising half-metallic material to generate spin current in spintronic devices.