Berlin 2015 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

MM: Fachverband Metall- und Materialphysik

MM 22: Functional Materials IV: Thermoelectric and Multiferroic Materials

MM 22.4: Vortrag

Dienstag, 17. März 2015, 11:00–11:15, TC 010

Microscopic model of paralectric/ferroelectric perovskites — •Giovanni Pizzi¹, Andrea Cepellotti¹, Boris Kozinsky², and Nicola Marzari¹ — ¹Theory and Simulation of Materials (THEOS) and National Center for Computational Design and Discovery of Novel Materials (MARVEL), EPFL (CH) — ²Robert Bosch LCC Research and Technology Center, Cambridge (USA)

Even if ferroelectric materials like BaTiO₃ have been used for decades in a broad range of technological applications, there is still significant debate in the literature concerning their microscopic behavior. In particular, many perovskite systems display a high-temperature cubic phase with zero net polarization, whose microscopic nature is though still unclear. Indeed, some of these perovskite systems display a complex energy landscape with multiple local minima. Using our high-throughput platform AiiDA (www.aiida.net) to manage all calculations, we perform a study on a set of representative ABO₃ perovskites. We use spacegroup techniques to systematically analyze all possible local displacement patterns that are compatible with a net paraelectric phase, together with DFT calculations to assess the energetics and the stability of these patterns. Using this technique, we are able to describe the different classes of microscopic models underlying the perovskite systems.