ABSTRACT
Multiferroics are a relatively rare class of multifunctional materials that simultaneously exhibit several ferroic orders among ferromagnetic, ferroelectric, and ferroelastic. Given the scarcity of compounds that present two or more strictly ferroic orders, antiferroic orders are usually considered. Since the renaissance of multiferroics in 2003, much effort has been made to decipher the complex physical mechanisms at the origin of the magnetoelectric coupling. In intrinsic magnetic tunnel junctions, the two-order parameters (magnetization and polarization) of the multiferroic tunnel barrier determine the transport properties. En route to the grand objective of a magnetoelectrically controllable spintronics device, a lot has been learned on the physical properties of multiferroics, especially in thin film form. The field is at the confluence of several very active areas, such as spintronics, oxide interfaces, and nanoscale ferroelectrics; and advances are thus partly fueled by the fast progress made on the topics.
