Effect of the pinning of domain boundaries in Rb2ZnCl4 crystal near the curie point

Abstract

The contributions to the amplitudes of the harmonic components of the output signal of the Soyer-Tower circuit from charging the reference capacitor with capacitive current and the conduction current of an investigated specimen are separated via the harmonic analysis of repolarization in a Rb2ZnCl4 crystal in the ferroelectric phase near the phase transition temperature T c . Harmonic analysis of the dielectric hysteresis loops obtained when the specimen was affected by an electric field whose intensity E in changed according to harmonic law with amplitude E m showed that at E m > E coer (where E coer is the intensity of the coercive field), the process of repolarization starts and stops when E in reaches values of E m sin(φ0 − α0) and E m sin(φ0 + α0), respectively (where φ0 is the shift of phases between the voltage of the harmonic signal source and the voltage of the first harmonic in the reference capacitor in the Soyer-Tower circuit, and α0 is the phase corresponding to the normalized duration of repolarization). When the current value of intensity E in coincides with E c = E m sinφ0, the direction of polarization reverses. The increase in E c when T c is approached is shown to be the reason for the anomalous temperature-independent behavior of E coer.