Influence of elastically pinned magnetic domain walls on magnetization reversal in multiferroic heterostructures

Abstract

In elastically coupled multiferroic heterostructures that exhibit full domain correlations between ferroelectricand ferromagnetic subsystems, magnetic domain walls are firmly pinned on top of ferroelectric domainboundaries. In this work, we investigate the influence of pinned magnetic domain walls on the magnetizationreversal process in a Co40Fe40B20 wedge film that is coupled to a ferroelectric BaTiO3 substrate via interfacestrain transfer.We show that the magnetic field direction can be used to select between two distinct magnetizationreversal mechanisms, namely, (1) double switching events involving alternate stripe domains at a time or(2) synchronized switching of all domains. Furthermore, scaling of the switching fields with domain widthand film thickness is also found to depend on the field orientation. These results are explained by considering the dissimilar energies of the two types of pinned magnetic domain walls that are formed in the system.