Room-temperature ferromagnetic half metal in (C, Mn) co-doped orthorhombic ZnO with large magneto-crystalline anisotropy energy

Abstract

Room-temperature ferromagnetic (FM) half-metallic materials are essential for spintronics applications. Here, we find that (C, Mn) co-doped orthorhombic ZnO (termed (C, Mn) @Orth-ZnO) is a room-temperature FM half-metal with a magnetic moment of 3μ B per Mn atom. A detailed investigation of the electronic structure of the (C, Mn) @Orth-ZnO system demonstrates that the FM interaction originates mainly from the p–d exchange hybridization between the C2p and Mn3d states. Moreover, the induced extended spin-polarized states of nonmetallic C can mediate the long-range FM exchange interactions beyond the nearest-neighbor situation. The Curie temperature T C of the (C, Mn) @Orth-ZnO system is 371 K based on the mean-field approximation. The (C, Mn) @Orth-ZnO system also has a large magnetic anisotropy energy of 0.63 meV, which is mainly attributed to (dyz, dz 2) orbitals of the Mn atom. Finally, we discuss the influence of carrier concentration and external strain on the stability of the ferromagnetism of the (C, Mn) @Orth-ZnO system. We highlight the application prospects of (C, Mn) @Orth-ZnO in practical spintronic nano-devices.