Non-Debye relaxation and the glassy behavior of disordered perovskite ferroelectrics

The dielectric properties of compositional disordered perovskite ferroelect rics (1 - x)Pb(Mg1/3Nb2/3)O-3-xPbTiO(3) (x = 0.00, 0.10, 0.20, 0.40) were i nvestigated as a function of temperature and frequency. The non-Debye relax ation of Pb(Mg1/3Nb2/3)O-3 was observed clearly around the temperature of t he dielectric permittivity maximum (T-m). The frequency dependence of T-m w as analyzed using a generalized Arrhenius relationship omega = omega(0) exp [-(T-0/T-m)(p)]. For relaxors with different compositions, a clear change i n dynamic behavior can be indicated by the power parameter p, which is rela ted to the growth of interactions between polar microregions. The degree of dielectric relaxation and degeneration of the compositions from relaxer fe rroelectrics to normal ferroelectrics can be explained by the interaction o f polar microregions. (C) 1999 Published by Elsevier Science Ltd. All right s reserved.