| Abstract Scope |
Dislocations in ionic crystals and semiconductors can carry charges. In this presentation, I present observations of (1) dislocation motion controlled solely by using an external electric field in single-crystalline ZnS—the dislocations can move back and forth, depending on the direction of the electric field. (2)I will provide both experimental evidence and atomic simulations for reduced dislocation mobility in semiconductors under UV light. By combining photo-nanoindentation, transmission electron microscopy (TEM), and atomic simulations, we visualized dislocation distribution in both darkness and under illumination. (3) We reveal 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. I will present results in other ionic crystals and semiconductors. |