First-principles study on ferromagnetism in Mn-doped tetragonal BiFeO3

First-principles calculations are performed to investigate the ferromagnetism in Mn-doped tetragonal BiFeO3. Different Mn distribution configurations were studied in G-and C-type antiferromagnetic BiFeO3. It was found that Mn atoms prefer to substitute for the neighboring Fe ions and display a robust ferromagnetic coupling. Electronic structure calculations indicated that Mn dopant changed the spin-polarized state of neighboring O atoms, which mediated the ferromagnetism coupling of Mn ions through the hybridization between Mn-3d, Mn-4p and O-2p orbitals. Further investigation indicated O vacancies have large effect on the ground magnetic ordering of Mn-doped BFO. (C) 2015 Elsevier B.V. All rights reserved.