Loparite-(Ce), A Natural Ferroelectric With The Perovskite-Type Structure

We report on the results of studies of dielectric properties of loparite-(Ce), a naturally occurring member of the perovskite-type family of materials, in the temperature range of 80-400 K. A strong frequency dispersion attributable to disorder and a dielectric anomaly have been observed in the vicinity of T = 157 K. The behavior of the inverse dielectric permittivity 1/epsilon'(T) has been found to be well described by the Curie-Weiss law with parameters C = 2.2 x 10(5) K-1 and T-m = 157 K. Studies of a dielectric hysteresis demonstrated the presence of ferroelectric loops below T-m approximate to 157 K, which points to the existence of a ferroelectric phase transition at T-m. The behaviors of spontaneous polarization, remanent polarization, and coercive field indicate that the ferroelectric phase transition is of the first-order type. (C) 2014 AIP Publishing LLC.