Phase stability after an electric-field poling in Pb(Mg 1/3Nb2/3)1-xTixO3 crystals

Abstract

This work concerns phase thermal stability in (001)-cut Pb(Mg 1/3Nb2/3)1-xTixO3 crystals after an electric (E)-field poling, which is crucial for piezoelectric applications. Dielectric properties have been measured as functions of Ti content (x=24, 26, 27, 29, 35, and 38%), E-field strength, temperature, and poling process. Domain structures after poling have also been observed by polarizing microscopy. An extra dielectric anomaly, which is mostly associated with the appearance of monoclinic domains, was observed during zero-field heating after poling. A prior poling can reveal a "hidden" phase transition which was not clear in unpoled samples. The monoclinic phase plays an essential role in bridging higher symmetries while phase transitions are taking place.