Dynamical properties of the relaxor ferroelectric 0.71Pb(Ni1/3Nb2/3))O3-O.29PbTiO3 probed by Brillouin and Raman scattering.

Abstract-Structural phase transitions in relaxor ferroelectric materials remain to be one of the most puzzling issues in materials science. In the present work, we have investigated relaxational and vibrational properties of a relaxor ferroelectric 0.71Pb(Ni(1/3)Nb(2/3))O(3)-O.29PbTiO(3) single crystal by means of inelastic light scattering measurements. Analysis based on the spectra has shown anomalous behaviors at Burns' temperature T(d), freezing temperature T(f) , those are related to a development of polar nanoregions (PNRs). The PNR must play a key role in the relaxor nature, and obtained results provide new insights into the relaxational dynamics in the PNRs and into how they develop below T(f).