Bias-field effect on the temperature anomalies of dielectric permittivity in PbMg1/3Nb2/3O3-PbTiO3 single crystals

Abstract

In contrast to ordinary ferroelectrics where the temperature T-m of the permittivity maximum monotonically increases with bias field E in (1-x)PbMg1/3Nb2/3O3-(x)PbTiO3 (0 <= x <= 0.35) single crystals, T-m was found to remain constant or to decrease with E up to a certain threshold field E-t, above which T-m starts increasing. The threshold field E-t decreases with increasing x, tending toward zero at approximately x=0.4. We explain this dependence in the framework of models which take into account quenched random fields and random bonds. For crystals with 0.06 <= x <= 0.13, the E-T phase diagrams are constructed. In contrast to PMN, they exhibit an additional, nearly field-independent boundary, in the vicinity of the Vogel-Fulcher temperature. We believe this boundary to correspond to an additional phase transition and the appearing order parameter is likely to be nonpolar.

Description

Keywords

Lead magnesium niobate, Phase transitions, Electric fields, Relaxers, Ferroelectrics, Zirconate-titanate, Polarized raman, States, Model, Susceptibility, Perovskites, Physics

Citation

Raevski, IP ; Prosandeev, SA ; Emelyanov, AS ; et al., Nov 2005. "Bias-field effect on the temperature anomalies of dielectric permittivity in PbMg1/3Nb2/3O3-PbTiO3 single crystals," PHYSICAL REVIEW B 72(18): 184104. DOI: 10.1103/PhysRevB.72.184104