Influence of defects on the properties of a 2D ferroelectric:: A Monte-Carlo simulation study

In this article, Monte-Carlo simulation methods were used to investigate the influence of different types of defects on the properties of a 2-dimensional ferroelectric. To this end, a recently published model by B. G. Potter et al. [J. Appl. Phys. 87 (2000) 4415] was extended to include simple defects. The effect of these defects on the hysteresis curves was analyzed. The interaction of a single domain wall with a defect cluster was also investigated with this model. Furthermore, the simulation could be used to verify the dependence of the Rayleigh constant on the defect concentration, predicted by Boser [J. Appl. Phys. 62 (1987),1344] theoretically and recently found to be valid for donor-doped lead zirconate titanate (PZT) thin films [Bolten et al., Appl. Phys. Lett. 77 (2000) 3830]. The simulation provided evidence for the existence of a defect-driven relaxation process in ferroelectrics similar to the relaxation found in heavily disturbed systems.