Phase Transition Effect on Ferroelectric Domain Surface Charge Dynamics in BaTiO3 Single Crystal.

Dongyu He,Wenbo Du,Jian Liu,Pengfei He,Xiujian Tang,Yuxin Liu,Haidou Wang

doi:10.3390/ma14164463

Abstract

The ferroelectric domain surface charge dynamics after a cubic-to-tetragonal phase transition on the BaTiO3 single crystal (001) surface was directly measured through scanning probe microscopy. The captured surface potential distribution shows significant changes: the domain structures formed rapidly, but the surface potential on polarized c domain was unstable and reversed its sign after lengthy lapse; the high broad potential barrier burst at the corrugated a-c domain wall and continued to dissipate thereafter. The generation of polarization charges and the migration of surface screening charges in the surrounding environment take the main responsibility in the experiment. Furthermore, the a-c domain wall suffers large topological defects and polarity variation, resulting in domain wall broadening and stress changes. Thus, the a-c domain wall has excess energy and polarization change is inclined to assemble on it. The potential barrier decay with time after exposing to the surrounding environment also gave proof of the surface screening charge migration at surface. Thus, both domain and domain wall characteristics should be taken into account in ferroelectric application.

Highlights

The development of ferroelectric materials has promoted promising applications in non-volatile storage devices [1,2,3], sensors and actuators [4,5], and infrared detector systems [6,7]
We introduced the SKPFM study of domain structures and dynamic behaviors of BaTiO3 single crystal after a cubic-totetragonal phase transition
The phase transition of BaTiO3 crystal leads to the surface morphology and surface charge distribution change that observed in the Scanning probe microscopy (SPM) images (Figure 1)

Summary

Introduction

The development of ferroelectric materials has promoted promising applications in non-volatile storage devices [1,2,3], sensors and actuators [4,5], and infrared detector systems [6,7]. The ferroelectric domain structure is the fundamental execution unit of ferroelectrics [8]. The Curie temperature [9], ferroelectrics have spontaneously polarized domains and their ability to switch with the external field is the most important feature in ferroelectric physics [10,11]. Surface charges can reflect the underlying domain polarity characteristics [12]. Temperature and surface charges affect the polarization dynamics and domain structures. Studying the change of ferroelectric domain performance with temperature has great scientific and engineering significance, for as electronic components, ferroelectrics always work in a certain temperature field environment [13,14,15]

Methods

Results

Conclusion