A Review of Experimental Methods for Characterizing Ferroelectric Domain Dynamics in Relaxor-PbTiO3 Single Crystals

Relaxor-based ferroelectric single crystals possess colossal piezoelectric and dielectric properties and have been attractive for a wide range of electromechanical applications including transducers, sensors, and actuators. However, domain dynamics of relaxor ferroelectric single crystals are still not fully understood despite significant progress in the last three decades, partly because of the combined relaxor and normal ferroelectrics with complex domain structures within the material. Without a comprehensive understanding of domain dynamics, rational domain engineering for high piezoelectricity is challenging. In this review, we review experimental methods for characterizing domain dynamics in nanoscale and bulk mesoscale that exhibit both intrinsic and extrinsic contributions. We focus on literature published since 2010 and critically evaluate their strengths and limitations. From an overview of recent understanding, we highlight the need for real-time observations at appropriate time and length scales and cross-validation of different methods for precise measurements of domain dynamics.