Interface robust magnetoelectric coupling effect in ferromagnetic/ferroelectric BiFeO3/KNbO3 heterostructure: First-principles calculations

Abstract

Exploring strong interface magnetoelectric coupling properties of perovskite oxide heterostructures has important physical significance, which provides new opportunities for the design of the next generation of nanoscale electronic devices and magnetic storage devices. In this work, an effective method toward achieving non-volatile electrical control of two-dimensional magnets has been demonstrated. For example, when a heterostructure composed of multiferroic BiFeO3 and ferroelectric KNbO3 has been constructed, the magnetic order of BiFeO3 changes from antiferromagnetism to ferromagnetism by reversing the polarization direction of KNbO3, showing strong magnetoelectric coupling properties. The polarized states − P KNbO3 does not change the insulativity of BiFeO3 films, but + P KNbO3 makes BiFeO3 films half metal. This may enable non-volatile electrical control of BiFeO3 films between antiferromagnetic insulator and half-metal. This work paves the way for nonvolatile electrical control of two-dimensional heterostructure and applications in spintronics devices.

Keywords

• First-principles
• Magnetoelectric coupling
• Ferroelectric polarization
• Heterostructure