Micro–macro correlation in ferroelectric materials: Depolarization mechanism for different excitations

In this study, X-ray diffraction was used to describe the depolarization mechanism of ferroelectric materials by the application of compressed stress or electric field. By this microscopic method, 90° domain reorientation can be quantified and distinguished from 180° domain switching. Experimental polarization and strain variations were simulated from microscopic data and details on micro–macro relationships were given. It was found that, under an electric field, ferroelectric compounds exhibit 180° domain switching (one step) and two types of 90° domain switching. This work reveals these three different switching processes in order to explain the depolarization mechanism with compressed stress and electric field. Kinetic aspects of domain walls motion and nucleation of domains have also been studied.