Ferroelectric Domain Structure And Polarization Reversal Of Computer Simulation,

Ferroelectrics have attracted great interest due to their excellent properties. It is important to understand the origin of the ferroelectricity for finding new functional ferroelectrics. Experimental and theoretical studying of the ferroelectric domains is important to understand the polarization and related physics properties. The previous investigations on the ferroelectric domains have two parts: one is studying the domain structures by the principle of minimization of the free energy and Curie principle, which including the size of domains, domain walls and tropism of the near domains; another is by dynamic method.The recent work on simulating the domain structure is mainly by Ising model. The results from the simulating works are much different to experimental ones. Moreover, it could not reflect the longnitudinal growth the domain. The present simulating work which including the fourth spin interaction would directly show the figure of the domain structure change with the external electric field and how the ferroelectric domains reverse. The present results agree well with the experimental ones.In this following, I summarize the main contents and findings in my dissertation.(1) Simulating of the neighbor and fourth spin interaction effect on ferroelectric domain structures. I include the nearest neighbors spin interaction, the interaction between the sub-near spin and nearest spin, and the interaction among the nearest, sub-near and third near spin step by step and study the dynamical evolvement of the ferroelectric domain and polarization reversion within Monte Carlo method, and discuss the relation between polarization and external field. The...