Decodo: Defect complexes and domain walls an ab initio based scale-bridging study on ferroelectrics

• Applicant: Professorin Dr. Anna Grünebohm
• Subject Area: Computer-Aided Design of Materials and Simulation of Materials Behaviour from Atomic to Microscopic Scale
• Term: since 2025
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 560576428

Due to the sensitivity of their polarization to external stimuli, ferroelectric perovskite oxides are essential for applications related to sustainable energy generation, conversion and storage, as well as for emerging communication and computing architectures. All these applications require control of the functional response at the nanoscale, which is closely linked to the properties of domain walls. The Decodo project aims to control ferroelectric switching processes and the motion, pinning, and character of domain walls through point defects. Starting from the technically relevant model system of transition metal doped BaTiO3, we will predict rules for the selection, distribution, and density of point defects to tailor domain walls and their response to external fields. Despite the high technological relevance, the systematic comparison of different point defects is missing in the literature, and the microscopic understanding of the defect-domain wall interaction is only rudimentary, especially in the orthorhombic ferroelectric phase. Since switching and wall motion are thermally activated processes on the nanoscale that are sensitive to the local electronic and atomistic structure, in Decodo we combine coarse-grained and atomistic molecular dynamics simulations with density functional theory to gain the fundamental understanding needed for material design.

• DFG Programme: Research Grants