First-principles prediction of the magnetism of 3 d transition-metal-doped Rocksalt MgO

Abstract

Using first-principles band structure methods, we have systematically studied the electronic structures, magnetic stabilities, and half-metal properties of 3 d transition-metal ( TM) doped Rocksalt MgO compounds TMMg 3O 4 ( TM = V , Cr, Mn, Fe, Co, and Ni). The calculations reveal that only CrMg 3O 4 has a ferromagnetic stability among the six compounds, which is explained by double-exchange mechanism. The magnetic stability is affected by the doping concentration of TM if the top valance band is composed of partially occupied t 2 g states. In addition, CrMg 3O 4 is a half-metallic ferromagnet. The origins of half-metallic and ferromagnetic properties are explored. The Curie temperature ( T c ) of CrMg 3O 4 is 182 K. And it is hard for CrMg 3O 4 to deform due to the large bulk modulus and shear modulus, so it is a promising spintronic material. Our calculations provide the first available information on the magnetic properties of 3 d TM-doped MgO.