Monte-Carlo simulation on the dipole alignment in ferroelectric square lattice

The dipole alignment configuration in a multi-domained ferroelectric lattice of cubic symmetry is simulated using the Monte-Carlo method based on the Ginzburg-Landau model. It is revealed that the gradient energy associated with the spatial discontinuity of the dipole alignment near the domain walls results in not only 90degrees-domain configuration, but also distorted dipole alignment. The simulation shows that such a distorted alignment pattern is thermodynamically preferred at low temperature. The effect of the alignment distortion on the ferroelectric phase transition is discussed. It is found that a state number Q = 16 is enough for a reliable simulation of the distorted alignment of dipoles. (C) 2004 Elsevier B.V. All rights reserved.