Monte-Carlo simulation on domain patterns in ferroelectric model lattice

The domain formation and structures in a ferroelectric tetragonal model system in which the dipole-dipole interaction and gradient domain wall energy are taken into account is studied using Monte-Carlo method. It is revealed that the 90 deg. -domain walls with preferred head-to-tail dipole alignment coexist with the 180 deg. -walls in the domain configuration. The dipole-alignment patterns at various temperatures and system parameters are investigated, indicating clearly the suppression in magnitude of dipoles on the domain walls in order to lower the system free energy. The effect of temperature and gradient wall energy on the hysteresis loop is also simulated