Electric Field Control of Magnetism Based on Elastically Coupled Ferromagnetic and Ferroelectric Domains

This chapter presents a summary of recent findings on elastically coupled domains in multiferroic heterostructures that consist of a ferromagnetic film and a ferroelectric BaTiO3 substrate. The modification of structural symmetry at ferroelastic domain walls of a ferroelectric material creates magnetoelastic anisotropy boundaries in an adjacent ferromagnetic film via inverse magnetostriction. Magnetic domain walls are strongly pinned by these sudden anisotropy changes and, consequently, strong elastic coupling between magnetic and ferroelectric domain walls is obtained. The application of an electric field to multiferroic heterostructures changes the direction of polarization and thereby the in‐plane lattice structure of the ferroelectric layer. Via inverse magnetostriction, this alters the magnetoelastic anisotropy of the adjacent ferromagnetic film. The chapter reviews electric field control of ferromagnetic domains for a1‐a2 stripe patterns. It then discusses electric field driven magnetic domain wall motion in heterostructures with a‐c domains.