Regensburg 2022 – wissenschaftliches Programm
KFM 1.3: Tutorium
Sonntag, 4. September 2022, 17:30–18:15, H3
Atomic scale analysis of ferroic domain walls — •Shelly Conroy — Department of Materials, London Centre of Nanotechnology, Imperial College London, United Kingdom
The dynamic interfaces of ferroic materials known as domain walls by-pass the static limitations of traditional nano-device designs. In contrast to hetero-interfaces between different materials, domain walls can be created, moved and removed via an applied stimulus. By combining multiple ferroic properties such as electricity and magnetism, new multi-functional interactive device applications are possible. As these mobile walls can be atomically sharp, it is essential to have physical characterisation at this scale spatially and time-resolved. In this tutorial, I will give an introduction to electron microscopy techniques starting with how to identify domain patterns in the bulk samples, and the most appropriate electron microscopy techniques to use with increasing magnification, leading to pico-meter characterisation. We will discuss some of the most recent advances in electron microscopy characterisation methods for ferroelectrics such as visualising electric charge density at sub-angstrom resolution, and the benefits of coupling polarisation characterisation with electron energy loss spectroscopy band structure analysis. We will then talk about how one can probe multiferroic properties such as magnetic field, strain and phonon modes. As one of the most exciting aspects of ferroic domain walls is their mobility, the various in situ options to investigate their dynamics will be detailed.