Engineering Enhanced Piezoelectric Response

The piezoelectric effect is a useful property of certain crystals where the application of pressure on a crystal produces a voltage, and conversely in the inverse piezoelectric effect, the size of the crystal changes with the application of voltage. Piezoelectricity is widely used in devices such as ultrasound machines and various sensors and actuators. This thesis presents the development of two arti-ficially layered material systems with enhanced piezoresponse and techniques developed to accurately characterize functional proper-ties. Large piezoelectric responses, such as those seen in PbZrxTi1−xO3 in the vicinity of the compositional morphotropic phase boundary, can occur when the direction of the polarization in a ferroelectric material can rotate. Here we combine PbTiO3, a ferroelectric with out-of-plane polarization when grown on SrTiO3, and CaTiO3, a ferroelectric with in-plane polarization when grown on SrTiO3, int