2D and 3D STEM Imaging and Spectroscopy: Applications and Perspectives in View of Novel STEM Infrastructure

Atomic-resolution imaging with a spherical aberration-corrected scanning transmission electron microscope (STEM) is now widely used for the study of interesting, complex material systems. This is owed both to the flexibility in detecting the electrons scattered off from matter, and also to the improved efficiency in collecting spectroscopic signals. To name a few topics: Understanding transport properties (such as charge localization, band versus ballistic transport or the interplay between lattice strain, band structure and charge transport…). Fundamental aspects of spintronics (such as the interplay of structure, chemistry and defects and their role in complex oxides, doped semiconductor materials and other nanostructures,…). Understanding the physics fundamentals of photonic materials (such as excitonic or polaronic coupling, photonic density of states 3D reconstructions, …). In materials science: Improving and understanding defect-engineering (such as the role of dislocations, and remedies to improve mobilities in electro-active materials…) or the understanding of phase formations and transitions (like precipitation formation in metals and alloys, role of coatings and additives of precursor powders used in 3D printed materials…). Overall, the STEM can provide numerical data on some key properties of matter. Recently, the FELMI/ZFE proposed a new instrument, going beyond the standard specifications of common STEMs. Three key characteristics will make this instrument outstanding:
performance, flexibility, and throughput. The talk aims to give an overview of 2D and 3D spectroscopic imaging, by showcasing some highly topical research questions on selected material systems in the light of the future hardware infrastructure.