Chiral domains in cycloidal multiferroic thin films: switching and memory effects.
ABSTRACT Cycloidal magnetic order occurring in some AMnO(3) perovskites is known to induce ferroelectricity. The polarization is perpendicular to the propagation vector direction of the cycloid and its chirality, and therefore it is directly related to the chiral domain structure. We show that the switching process of chiral domains is sensitively dependent on the magnetoelectric history of the sample. Moreover, by appropriate field cycling, magnetic order can display partial chiral memory. We argue that memory results from electric field coupling of cycloidal domain and nucleation and pinning of chiral domain walls, much like the domain structure in other ferroic systems.