LAUSR

Ferroelectric-dielectric composite materials are attractive for a range of applications in future functional devices. Here, we utilized a free energy based computational approach to investigate the electric-field driven response of isolated ferroelectric nanoparticles embedded in a dielectric matrix and its dependence on particle size, shape, and orientation of the applied field E. Particle shapes belonging to the superellipsoidal family were considered, including octahedral, spherical, and cuboidal structures, as well as a number of intermediate geometries. Perovskite PbTiO 3 and SrTiO 3, respectively, were chosen as the prototypical ferroelectric and dielectric materials. In particles of all shapes that are large enough to support domain walls at zero applied field, we observed polarization switching by a formation of intermediate phases, which possess an appreciable amount of vorticity stemming from the domain wall motion through the ferroelectric inclusion volume. The system coercive field E c and energy storage efficiency were found to be strongly dependent on the particle shape and the orientation, but not on its size. In near spherical particles with easy polarization axis pointing away from the direction of E, smallest E c and highest storage efficiencies were obtained, while nonspherical particles with aligned easy polarization and E directions exhibited highest E c and relatively low energy storage efficiencies.Ferroelectric-dielectric composite materials are attractive for a range of applications in future functional devices. Here, we utilized a free energy based computational approach to investigate the electric-field driven response of isolated ferroelectric nanoparticles embedded in a dielectric matrix and its dependence on particle size, shape, and orientation of the applied field E. Particle shapes belonging to the superellipsoidal family were considered, including octahedral, spherical, and cuboidal structures, as well as a number of intermediate geometries. Perovskite PbTiO 3 and SrTiO 3, respectively, were chosen as the prototypical ferroelectric and dielectric materials. In particles of all shapes that are large enough to support domain walls at zero applied field, we observed polarization switching by a formation of intermediate phases, which possess an appreciable amount of vorticity stemming from the domain wall motion through the ferroelectric inclusion volume. The system coercive field ...