IMX Colloquium - Domain walls in multiferroics and multiferroic domain walls

A reason for the interest in multiferroics is that magnetic and electric orders do not simply exist side by side, but exhibit "added value" in the form of magnetoelectric interactions and functionalities between the ordered states. Likewise, in a ferroic material, regions with different orientation of the order parameter, the domains, do not simply exist side by side, but they exhibit new phases and properties in the domain walls. Because of their discontinuous, confined, and topological nature, domain walls exhibit functional states that are not possible in the bulk. Continuing this line of thought, one should expect domain walls in multiferroics to be a particularly rich source of novel phenomena. Here one must distinguish between (i) "domain walls in multiferroics", where only the ferroelectric (or magnetic) order is considered so that little is learned about the multiferroic state, and (ii) "multiferroic domain walls" where the ferroic phase coexistence of the wall itself is of interest. The latter are rarely studied, and I will discuss some of their intriguing features in my talk.

Bio: Professor Manfred Fiebig is known for his work in light-matter interaction in systems with strong electronic correlations. (Multi-) ferroics are of particular interest to him. After obtaining his doctoral degree in physics at the University of Dortmund, he worked at the University of Tokyo, the Max Born Institut Berlin, and the University of Bonn before he was appointed as Professor of Multifunctional Ferroic Materials in the Department of Materials at ETH Zurich in 2011. In 2021 he also became a member of the National Research Council of the Swiss National Science Foundation (SNSF), and he was elected as Corresponding Member of the Academy of Sciences and Literature | Mainz. Most recent distinctions include the 2022 APS Frank Isakson Prize for Optical Effects in Solids as well as the of the Stern Gerlach Medal in 2023, the highest distinction in Experimental Physics of the German Physical Society. He is one of the founders of the ETH Spinoff Company “3Wave Instruments”.