Modelling non-exponential polarization relaxations in interacting dipole systems

摘要

Relaxational polarization processes of many polar dielectrics can be described in the time domain by stretched exponential functions which is referred to as Kohlrausch behaviour. For an interacting system of statistically distributed permanent dipoles arranged between two coplanar electrodes numerical calculations of the transient polarization curves are performed showing these long lasting relaxations. The electrostatic dipole-dipole interaction is considered and the electrodes are taken into account using the method of image dipoles. The dipoles are fluctuating thermally activated in double well potentials according to the Boltzmann statistics. The computation is based on deterministic local field calculations and on weighted probabilistic dynamic Monte Carlo steps. In this paper we focus on the small signal response after applying a step function of the electric field. (c) 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.