Polarized micro-Raman study of the field-induced phase transition in the relaxor 0.67PbMg1/3Nb2/3O3–0.33PbTiO3 single crystal.

Polarized Raman spectroscopy has been performed to investigate the effects of the electric field on 0.67PbMg_1/3Nb_2/3O₃–0.33PbTiO₃ (PMN–33%PT) single crystal. The electric-field-evolution of Raman spectra differed from one microarea to another. In the crossed polarization geometry, the abrupt changes in the intensities of the Raman bands at around 570 and 780 cm^-1 indicated the occurrence of the field induced phase transition from the M_C-type to the M_A-type monoclinic structure. On the other hand, the Raman spectra for the microarea that was initially in the M_A phase exhibited no obvious changes. All these results revealed the microheterogeneity in PMN–33%PT single crystal, which is useful for understanding the field-induced superior electromechanical properties. [ABSTRACT FROM AUTHOR]