Dr. Yijia Gu
Missouri University of Science and Technology
Ferroelectric materials are a class of materials that exhibit spontaneous electric polarization that can be reversed by an external electric field. These materials have unique electrical, mechanical, and optical properties, making them useful in a wide range of applications such as memory devices, sensors, actuators, and energy harvesting. In this presentation, we will present the phase-field model of ferroelectric materials. In this first part, the domain structure evolution during cooling and heating will be modeled. The stabilization of the metastable monoclinic phase and the mechanism of enhanced piezoelectric response will be elucidated. The second part of this presentation will focus on the flexoelectric effect, which describes the linear coupling between strain gradient and electric polarization and between the polarization gradient and strain. The effect of flexoelectricity on mechanical domain switching and domain wall structures will be analyzed by phase-field simulations.