Anomalous variations in elastic properties of lead zirconate niobate-lead titanate single crystals in the vicinity of its ferroelectric phase transition

作者：Shabbir G^*; Kojima S

来源：EPL, 2014, 105(5): 57001.

DOI：10.1209/0295-5075/105/57001

The acoustic phonon mode anomalies in the paraelectric phase of tetragonal and rhombohedral (1 - x)Pb(Zn1/3Nb2/3)O-3-xPbTiO(3) single crystals were systematically investigated by Brillouin light scattering measurements. The inverse relaxation time in the paraelectric phase of both crystals showed a stretched-type slowing-down temperature dependence approaching the structural phase transition temperature (T-C) instead of a normal critical slowing-down. The observed anomalous part of the elastic constant (c(11)) in the paraelectric phase of the tetragonal crystal in the vicinity of TC, exhibited a log(T - T-0/T-0)-type dependence in the temperature range from T-C to similar to T-C + 80 degrees C. On the other hand, the elastic constant of the rhombohedral ferroelectric crystal exhibited a deviation from such a temperature dependence. This was attributed to the interaction of acoustic phonon modes with strong polarization fluctuations and elastic deformation arising from the complex dynamics of polar nanoregions.

• 出版日期2014-3