First-principles study on magnetoelectric coupling effect of M/BiFeO3 (M = Co, Fe) multiferroic superlattice

Electronic structure and magnetoelectric coupling effect for M/BiFeO3 (M = Co, Fe) multiferroic superlattices are predicted by first-principles within the GGA + U. Hybridizations of O-2p and M-3d orbital are found on the interface of superlattices. The charge redistribution and ferroelectric polarization make magnetic moment different between the bottom and top interface, which results in the ME coupling effect. The magnetoelectric coupling coefficient of Co/BiFeO3 is bigger than that of Fe/BiFeO3 by comparing with their ferroelectric and magnetic properties.