The magnetism of Fe4N/oxides (MgO, BaTiO3, BiFeO3) interfaces from first-principles calculations

摘要

The geometry, bonding, electronic and magnetic properties of Fe4N/oxides (MgO, BaTiO3 and BiFeO3) interfaces with different configurations are performed using first-principles calculations. The n- and p-type doping of MgO are induced in (FeFeII)-Fe-I/MgO and (Fe-II)(2)N/MgO interfaces, respectively. The metallic characteristics are induced in BaTiO3 by contact with (FeFeII)-Fe-I termination, followed by p-type doping in the (Fe-II)(2)N/BaO interface and n-type doping in the (Fe-II)(2)N/TiO2 interface. The interfacial dipole due to charge rearrangement may induce the Fermi level pinning in the Fe4N/MgO and (Fe-II)(2)N/BaTiO3 systems. The deposition of Fe4N on BiFeO3 leads to a metallic character of BiFeO3 with total magnetic moments of 0.33-1.54 mu B. The different electronic and magnetic characters are governed by interfacial bonding between Fe4N and oxides. These findings are useful for the future design of Fe4(N)/oxides based spintronics devices.