Domain splitting and enhanced piezoelectricity in ferroelectric thin films with square grid structure

Abstract

The pattern evolution of the stripe-like domain structure in tetragonal ferroelectric thin films upon introduction of square void arrays is investigated using Monte Carlo simulation based on the Landau-Devonshire phenomenological theory. The regular splitting of the stripe-like domains near the voids and substantial release of both the dipole-dipole interaction and the electromechanical energy are revealed. Consequently, a significant enhancement of piezoelectric coefficient is predicted. It is suggested that the delicate balance between the two energy terms modulated by the void array periodicity and void size is responsible for the domain splitting. The present work proposes an alternative promising approach to tune the domain structure via simple micro-fabrication techniques.