Inversion of Ferrimagnetic Magnetization by Ferroelectric Switching via a Novel Magnetoelectric Coupling

Although several multiferroic materials or heterostructures have been extensively studied, finding strong magnetoelectric couplings for the electric field control of the magnetization remains challenging. Here, a novel interfacial magnetoelectric coupling based on three components (ferroelectric dipole, magnetic moment, and antiferromagnetic order) is analytically formulated. As an extension of carrier-mediated magnetoelectricity, the new coupling is shown to induce an electric-magnetic hysteresis loop. Realizations employing BiFeO₃ bilayers grown along the [111] axis are proposed. Without involving magnetic phase transitions, the magnetization orientation can be switched by the carrier modulation driven by the field effect, as confirmed using first-principles calculations.