Field induced O-M-C phase transition and domain structure evolution in Pb(Mg1/3Nb2/3)O-3-0.34PbTiO(3) single crystals under radial poling

摘要

Radial electric (E)-field induced periodic polarization rotation from orthorhombic (O) to M-C-type monoclinic (M-C) phase in Pb(Mg1/3Nb2/3)O-3-0.34PbTiO(3) (PMN-0.34 PT) single crystals has been studied by in situ polarized light microscope. The piezoelectric coefficient (d(33)*) and dielectric permittivity (epsilon(T)(33)/epsilon(0)) were 1800 pm/V and 5100, respectively, for [100]-oriented M-C samples, almost three times of those in [011]-oriented O phase crystals. The domain structure evolution from 10 to 4M(C) was confirmed based on the optical extinction rules and permissible domain configurations. Moreover, the phase transition sequences of [100]- and [011]-poled PMN-0.34 PT crystals were M-C-Tetragonal (T)-Cubic (C) and O-T-C upon heating, respectively. Our findings suggest that the phase stability of this crystals is associated with the orientation of applied field and radial E-field can serve as a general strategy to get fundamental insights into large piezoelectric activity and anisotropic phase stability in ferroelectric single crystals. (C) 2018 Elsevier B.V. All rights reserved.