Phase Diagram in Poled Samples of Pb(Zn_1/3Nb_2/3)O₃-PbTiO₃ Mixed Crystals

Abstract

Phase transitions in (1-x)Pb(Zn_1/3Nb_2/3)O₃-xPbTiO₃ (PZN-xPT) under the zero-field heating (ZFH) after the field cooling (FC) were investigated. It was confirmed that a sharp phase transition below the diffuse phase transition region in PZN under ZFH after FC appears at 114℃. Sharp phase transitions in PZN-xPT mixed crystals under ZFH after FC were also found near the morphotropic phase boundary (MPB). We concluded that these sharp phase transitions in PZN-xPT correspond to the one between the tetragonal and rhombohedral phases.