Brillouin and Raman scatterings of a 0.71Pb (Ni13 Nb23) O3 -0.29PbTi O3 single crystal have been measured to investigate broadband inelastic spectra. The two different central peaks related to fast and slow relaxation processes have been observed separately. These two processes are attributed to the thermally activated switching of polarization in polar nanoregions. By the analysis of modified superparaelectric model, the activation energies of fast and slow relaxation processes are determined to be 3.66× 103 and 4.31× 102 K, respectively. The fast process with the lower activation energy probably originated from 180° switching, whereas the slow one with the higher energy from non-180° switching.
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)