- 著者
- Ahart Muhtar Hushur Anwar Bing Yonghong Ye Zuo-Guang Hemley Russell J. Kojima Seiji
- 出版者
- American Institute of Physics
- 雑誌
- Applied physics letters (ISSN:00036951)
- 巻号頁・発行日
- vol.94, no.14, pp.142906, 2009-04
- 被引用文献数
- 27
Brillouin spectroscopy of Pb(Sc0.5Nb0.5)O3 single crystals reveals an order-disorder ferroelectric phase transition occurs at 110 °C upon cooling. A softening of the longitudinal acoustic (LA) mode is observed that can be attributed to the coupling between polar nanoregions and acoustic modes. A critical slowing down of the central peak, a feature of order-disorder ferroelectric phase transitions, is observed near Tc. The similarity in temperature dependences of the two kinds of relaxation times determined from the central peak and LA mode suggests that the changes in the central peak arise from local polarization fluctuations in the polar nanoregions.
- 著者
- Ko Jae-Hyeon Kojima Seiji Bokov Alexei A. Ye Zuo-Guang
- 出版者
- American Institute of Physics
- 雑誌
- Applied physics letters (ISSN:00036951)
- 巻号頁・発行日
- vol.91, no.25, pp.252909, 2007-12
- 被引用文献数
- 36 25
The dynamic polar nanoregions (PNRs) which form below the Burns temperature and determine the unique properties of relaxor ferroelectrics were predicted [Tinte et al., Phys. Rev. Lett. 97, 137601 (2006)] to be pinned to the quenched chemically ordered regions (CORs) usually observed in lead-containing relaxors. In Pb[(Mg1/3Nb2/3)0.45Ti0.55]O3 crystal where CORs are known to be absent, we have found the phenomena typically related to the relaxation of dynamic PNRs, namely, the significant Brillouin quasielastic scattering, the softening of the longitudinal acoustic mode, and the deviation from the Curie-Weiss law above the Curie point. This implies that PNRs may appear in crystals without CORs.