Dislocation Dynamics Under an Extreme Electric Field

For decades, the movement of dislocations has been widely observed in crystalline solids under mechanical loading. However, the goal of manipulating dislocation motion via a non-mechanical field alone remains elusive. In this presentation, I will present real-time observations of dislocation motion controlled solely by using an external electric field in ionic crystals —the dislocations can move back and forth depending on the direction of the electric field. This work reveals the non-stoichiometric nature of dislocation cores and determine their charge characteristics. Both negatively and positively charged dislocations are directly resolved, and their glide barriers decrease under an electric field, explaining the experimental observations. This study provides direct evidence of dislocation dynamics controlled by a non-mechanical stimulus and opens up the possibility of modulating dislocation-related properties.