On the elastically coupled magnetic and ferroelectric domains: A phase-field model

A phase-field model is developed to study local elastic coupling between magnetic and ferroelectric domains that show one-to-one pattern match. A multiferroic layered heterostructure of Co_0.4Fe_0.6/ BaTiO₃ is considered as an example. Dynamics of the local elastic coupling is investigated by simulating a time-dependent electric-field driven changes in local magnetization/polarization/strain distributions and by comparing the associated velocities of the magnetic and ferroelectric domain walls. It is found that the electric-field-driven dynamic magnetic domain evolution manifests itself as an alternating occurrence of local magnetization rotation and coupled motion of magnetic and ferroelectric domain walls with almost identical velocities.