Room temperature ferromagnetic half metal in Mn doped cluster-assembled sodalite phase of III-N compounds

Abstract For the next-generation spintronic nanodevices, it is highly desirable to explore the ferromagnetic (FM) half-metal materials with high Curie temperature (TC), wide half-metallic gap, and large magnetic anisotropy energy (MAE). Here, from density functional theory calculations, we predict two types of such materials in Mn doped III-N low-density cluster-assembled sodalite (SOD) phases. Specifically, SOD-(Al, Mn)N and -(Ga, Mn)N possess robust FM ground state with high TC temperature of up to 788 K and 633 K, respectively, due to the strong Mn-N exchange interaction. Both of their magnetic moments are calculated to be 4 μB per formula unit. They have large half-metal direct band gaps (1.70 eV and 1.33 eV for SOD-(Al, Mn)N and -(Ga, Mn)N, respectively, which can effectively prevent the spin-flip scattering during spin transportation, guaranteeing the application of half-metallicity at ambient temperature. Moreover, the MAEs of SOD-(Al, Mn)N and -(Ga, Mn)N are −0.56 and −0.53 meV per Mn atom, respectively, about two orders of magnitude larger than those of some traditional magnetic materials. Our findings highlight that the FM systems of SOD-(Al, Mn)N and -(Ga, Mn)N are the promising materials for the applications of spintronics.