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

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