Effect of ferroelastic twin walls on local polarization switching: Phase-field modeling

Local polarization switching in epitaxial ferroelectric thin films in the presence of ferroelastic domain walls was studied using phase-field approach. The nucleation bias profile across a twin wall was analyzed, and the localization of preferential nucleation sites was established. This analysis was further extended to a realistic domain structure with multiple twin boundaries. It was observed that the local nucleation voltage required for a 180 degrees domain switching is closely related to the number of such local defects. (C) 2008 American Institute of Physics. [DOI: 10.1063/1.2993330]