Dynamics of domain structure in uniaxial ferroelectrics

Abstract

The switching of polarization in ferroelectrics is considered as the first-order phase transition. By the analogy with the theory of crystal growth it is assumed that the switching process is determined by the oversaturation degree which correspond in ferroelectrics to the magnitude of electric field on the domain boundary. It is supposed that the mechanism of domain wall motion in strong field is due to the twodimensional nucleation and in weak field is due to the one-dimensional nucleation. The criterion of strong field IS defined. From this point of view it have been explained the peculiarities of domain structure dynamics in two uniaxial ferroelectrics: lead germanate and gadolinium molybdate.