Structure-Dynamics Correlation in Metallic Glass Revealed by 5-Dimensional Scanning Transmission Electron Microscopy

Abstract: Dynamic and structural heterogeneities play an important role in glass transition phenomena and in the formation of amorphous structures. Since structure and dynamics are mutually related, it is expected that there exists some relation between them; however, this relation has not been characterized by a direct experiment. Elucidation of this relation is the key to identifying the structure responsible for the rapid freezing of atomic motion during the glass transition. In this study, we simultaneously observed the dynamic and structural heterogeneities near the glass transition temperature in Zr50Cu40Al10 using five-dimensional scanning transmission electron microscopy, which is capable of recording the spatiotemporal distribution of electron diffraction pattern. Dynamic and structural heterogeneities were visualized with sub-nanometer resolution upon heating in situ, and a spatial correlation between them was observed up to the glass transition temperature. Simultaneous measurements of dynamic and structural heterogeneities directly revealed that the ordered atomic structure had slow dynamics and that the order decreased with temperature.