”Monte Carlo modeling of domain structures and switching properties in ferroelectric ceramics”, financed by the Romanian National Authority for Scientific Research, CNCS – UEFISCDI
Nr. contract: PD 160/2018
Project Director: Asist. univ. dr. Leontin PADURARIU
(Faculty of Physics, Alexandru Ioan Cuza University, Iași)
Ferroelectrics are multifunctional materials with a large applicability in microelectronics. The main characteristic of ferroelectrics is that, below a critical temperature (Curie temperature), they present spontaneous polarization and domain structure. This feature represents the physical origin of all macroscopic properties of ferroelectrics: switching (memory), nonlinear dielectric properties, piezoelectric, pyroelectric and electrooptic properties. Experimentally, it was demonstrated that ferroelectric domain structures are affected by many factors as: electrical and mechanical boundary conditions, average size of grains and boundaries in ceramics, the concentration and nature of the dopants in solid solutions, microstructural particularities in composites etc. Therefore, new materials with improved functional properties will be able to be produced, only by understanding the way these factors influence the domain structures. This goal can be achieved only by a modeling/simulation approach. In the last years, an intense research was dedicated in developing theoretical models able to describe properties of ferroelectrics at limited length scales, but a real breakthrough in the field would be realized by integrating these approaches into a complex multiscale model. The major objective of the project is to develop an innovative multiscale Monte Carlo model integrating Landau-Ginzburg-Devonshire theory and Finite Element Method, aimed to provide a powerful tool for describing ferroelectric properties of polycrystalline ceramics under realistic electrical and mechanical boundary conditions. During the project, the Monte Carlo model will be used to describe different fundamental problems of ferroelectricity: grain size effects, compositional effects in chemically inhomogeneous systems and microstructural effects in composites.