Large magnetoelectric coupling in ferromagnetic/ferroelectric superlattices with asymetric interfaces

•An approach is proposed to realize cumulative ME coupling in FM/FE superlattice.•A monolayer of different metal breaks inversion symmetry between the two interfaces.•We use FeM/PbTiO3 (M=Ni, Pt and Ag) as the model system to investigate the ME effects.•Combination of different ME coupling mechanisms produces large cumulative ME effect.

In this Letter, we investigate an attractive approach providing large and cumulative magnetoelectric coupling in ferromagnetic/ferroelectric superlattice by inserting a monolayer of different metal (ferromagnetic or normal metal) at one interface. Using first-principles calculations on FeM/PbTiO3 (M=Ni, Pt and Ag) as a model system, the recorded high magnetoelectric coefficients are obtained in one unit cell with the insertion of Ni and Pt monolayer. A carefully analysis reveals that the large magnetoelectric effects are determined by combinations of several different mechanisms including interface bonding, spin-dependent screening, and distinct type of magnetic interactions.