Recent Progress in the Study of Structure and Properties of Relaxor Ferroelectrics Near the Morphotropic Phase Boundary

In the region across morphotropic phase boundary (MPB), the single crystal form of lead-based relaxor ferroelectrics with perovskite structure shows superior dielectric and piezoelectric properties. Immense attention has been drawn because of its high application potentials. The characteristics of the abnormal properties of those single crystals were described in this review article. In addition, to explain the ultra-high electromechanical response, a theory of the polarization rotation mechanism was introduced in detail. In the same time the recent synchrotron X-ray powder diffraction measurements which revealed a monoclinic phase between the previously established tetragonal and rhombohedral regions were also introduced.