IMF2017

Over the last decade, the concept of strain engineering has proven to be extremely fruitful in generating new polar phases and tuning the functional properties of ferroelectric oxides. The temperature-strain phase diagrams of a number of ferroelectrics have been extensively studied, both experimentally and theoretically. Lead titanate based ferroelectrics in particular have received a large share of the attention, especially in the tensile strain region where polarisation rotation and complex ferroelastic domain patterns have been predicted and observed. The compressive regime, however, is less well explored. We have studied thin films of lead titanate deep in the compressive strain region of the phase diagram and report on a complex evolution of the structure and surface morphology observed with increasing film thickness as the material attempts to accommodate or relax the substrate-imposed epitaxial strain.