Simulation of thickness effect in thin ferroelectric films using Landau-Khalatnikov theory

The thickness effect in ferroelectric thin films has been theoretically investigated using the Landau-Khalatnikov theory. Ferroelectric properties such as the hysteresis loop, and its associated coercive field and the remanent polarization of various film thicknesses have been numerically simulated. In this simulation, the thin film was modeled by the stacking of layers, each of which has unique parameters for the Landau free energy. Due to the interfacial effects near the electrodes, the parameters for the surface layers are different from those for the bulk. The simulated result shows that the coercive field decreases while the remanent polarization increases with thickness. Both of these trends qualitatively agree with experiments. (C) 2003 American Institute of Physics.