Broadband inelastic light scattering study on relaxor ferroelectric Pb(In1/2Nb1/2)-Pb(Mg1/3Nb2/3)O-3-PbTiO3 single crystals

作者：Kim Tae Hyun; Kojima Seiji^*; Ko Jae Hyeon

来源：Journal of Applied Physics, 2014, 115(23): 234103.

DOI：10.1063/1.4878855

The broadband inelastic light scattering spectra of ternary Pb(In1/2Nb1/2)-Pb(Mg1/3Nb2/3)O-3-PbTiO3 single crystals were investigated as a function of temperature and crystal orientation by combining Raman and Brillouin spectroscopies. The angular dependence of the strong Raman peak located at similar to 50 cm(-1) was investigated at 300 degrees C. The intensity variation of this mode with rotation angle was compatible with the F-2g mode of Fm (3) over barm symmetry, suggesting that this mode arises from the 1: 1 chemical order at the B-site in this perovskite structure. The temperature evolution of the polar nanoregions was associated with the growth of two central peaks and the change in the intensity of some Raman peaks, which were known to be sensitive to the rhombohedral symmetry. Both relaxation processes exhibited partial slowing-down behaviors with a common critical temperature of similar to 160 degrees C. Poling the crystal along the [001] direction induced abrupt changes in some of the Raman bands at the rhombohedral-tetragonal phase transition. On the other hand, the diffuse tetragonal-cubic phase transition was not affected by the poling process. This high-temperature phase transformation seems to be smeared out by the inherent disorder and strong random fields enhanced by the addition of Pb(In1/2Nb1/2) into Pb(Mg1/3Nb2/3)O-3-PbTiO3.

• 出版日期2014-6-21