Author:
Margaritescu Irina,Liu Zenghui,Ye Zuo-Guang,Mihailova Boriana
Abstract
AbstractIn situ high-pressure/high-temperature Raman-scattering analyses on PbTiO$$_3$$
3
, 0.92PbTiO$$_3-$$
3
-
0.08Bi(Zn$$_{0.5}$$
0.5
Ti$$_{0.5}$$
0.5
)O$$_3$$
3
and 0.83PbTiO$$_3-$$
3
-
0.17Bi(Mg$$_{0.5}$$
0.5
Ti$$_{0.5}$$
0.5
)O$$_3$$
3
single crystals reveal an intensity transfer between the fine-structure components of the A$$_1$$
1
(TO) soft mode. The enhancement of the lowest-energy subpeak, which stems from intrinsic local non-tetragonal polar distortions, along with the suppression of the tetragonal A$$_1$$
1
(1TO) fundamental mode with increasing pressure and temperature indicates the key role of the local polarization fluctuations in transformation processes and emphasizes the significance of the order-disorder phenomena in both the pressure- and temperature-induced phase transitions of pure PbTiO$$_3$$
3
and its solid solutions with complex perovskites. Moreover, the temperature and pressure evolution of the fraction of the local non-tetragonal polar distortions is highly sensitive to the type of B-site substituent.
Funder
Universität Hamburg
National Natural Science Foundation of China
Natural Sciences and Engineering Research Council of Canada
Publisher
Springer Science and Business Media LLC