Anomalous Temperature Dependence of Electrostrictive Coefficients in K(Ta_0.55Nb_0.45)O₃

Abstract

A significant temperature dependence of the electrostrictive coefficients of K(Ta_0.55Nb_0.45)O₃ has been observed in a narrow temperature range above the ferroelectric Cuire point (T−T_C<30°C). The reciprocal permittivity versus temperature relation deviates from the Curie-Weiss law in the same temperature range. A simple model is proposed based on the polarization critical-fluctuation.