In situ synchrotron radiation topography study of the anomalous phase transition behavior in unpoled 0.92Pb (Zn1/3Nb2/3)O3–0.08PbTiO3 crystals

Through the unique white-beam synchrotron radiation topography (WBSRT) method with several Al foils covering the sample, we have investigated in situ phase transition behavior in unpoled relaxor ferroelectric 0.92Pb (Zn1/3Nb2/3)O3–0.08PbTiO3 (PZN–8%PT) crystals and found it was anomalous to that reported previously. According to the ferroelectric domain growth behavior on heating and cooling, it was demonstrated that the unpoled PZN–8%PT crystal undergone three phase transitions, i.e., the rhombohedral-orthorhombic (R–O) phase transition at 75 °C, the rhombohedral-monoclinic or orthorhombic–tetragonal (R–M/O–T) phase transition at 132 °C, and the monoclinic or tetragonal–cubic (M–C/T–C) phase transition at 262 °C. DSC analysis revealed that the R–O phase transition and the M–C/T–C transition was of the first-order, while the R–M/O–T one belonged to the second-order type.