Development of Ferroelectric Order in Relaxor (1-x)Pb(Mg1/3Nb2/3)O3 - xPbTiO3

TL;DR

This study investigates how the phase symmetry in relaxor ferroelectric PMN-xPT evolves with temperature and composition, revealing the emergence of a rhombohedral phase at low PT concentrations through synchrotron x-ray diffraction.

Contribution

It provides new insights into the structural evolution from relaxor to ferroelectric states in PMN-xPT by analyzing phase symmetry changes with composition and temperature.

Findings

Rhombohedral phase develops at PT concentration as low as 5%.

Structural evolution from relaxor to ferroelectric states is characterized.

High-resolution synchrotron x-ray diffraction reveals detailed phase transitions.

Abstract

The microstructure and phase transition in relaxor ferroelectric Pb(Mg1/3Nb2/3)O3 (PMN) and its solid solution with PbTiO3 (PT), PMN-xPT, remain to be one of the most puzzling issues of solid state science. In the present work we have investigated the evolution of the phase symmetry in PMN-xPT ceramics as a function of temperature (20 K < T < 500 K) and composition (0 <= x <= 0.15) by means of high-resolution synchrotron x-ray diffraction. Structural analysis based on the experimental data reveals that the substitution of Ti^4+ for the complex B-site (Mg1/3Nb2/3)^4+ ions results in the development of a clean rhombohedral phase at a PT-concentration as low as 5%. The results provide some new insight into the development of the ferroelectric order in PMN-PT, which has been discussed in light of the kinetics of polar nanoregions and the physical models of the relaxor ferroelectrics to illustrate the structural evolution from a relaxor to a ferroelectric state.