[en] In this paper, ceramics of pure barium titanate and barium titanate doped with manganese have been investigated. The temperature dependences of capacitance and heat capacity were measured. A comparison of the positions of the temperature maxima was carried out. Excess heat ΔQ) and excess entropy ΔS) of phase transitions were determined. The types of phase transitions for different samples were determined. An estimate of the spontaneous polarization of the samples was obtained by calorimetric measurements. (paper)

[en] The results of studies of the current-voltage characteristics of ceramic structures based on manganese doped barium titanate were presented. It was found that the electrical conductivity of ceramic samples based on barium titanate at high field strengths is determined by the Schottky emission. Moreover, the addition of manganese increases the resistance of the samples. (paper)

[en] The creation of devices based on the electrocaloric effect requires the methods for assessing pyroelectric currents at the different external parameters. Two indirect methods for calculating pyroelectric currents in ferroelectrics are considered. The first one based on the temperature-field dependences of the dielectric hysteresis loops. The second one based on the temperature-field dependences of the dielectric constant. The original method for directly estimating the magnitude of the pyroelectric currents by the charge change with thermal flux of laser radiation pulses is proposed. (paper)