In situ electron microscopy: modalities of dynamic measurements to capture fundamental physical or chemical processes down to the atomic scale

Since its birth, electron microscopy has touched on nearly every science and engineering discipline. Electron microscopy is an information-rich experimental method and sometimes appears rather intuitive as it visualizes the structure of materials ranging from micrometer to real atomic scale—it is often said that seeing is believing. As in many other areas of science and engineering, electron microscopy keeps on advancing both in instrumentation and software tools. In this chapter, an emerging part of electron microscopy suitable for studying dynamics in solids, whether by in situ or dynamic observation, is introduced. In situ electron microscopy explores the internal behavior of materials subjected to external stimuli such as heat, light, or external force, in real-time and submicroscopic scale. The technique provides an evidence-based understanding of the functional properties of new materials such as graphene and carbon nanotubes, the mechanical properties of structural metals and ceramics, the compositional deformation behavior of rocks that lead to the mechanism of earthquakes, and the vibration modes of polymers at the nanometer scale. This chapter provides a brief overview of the technique with a case study demonstrating experimental-computational integration and then discusses the on-going software tools development.