Atomic-resolution electron microscopic images of ruby show (0001) polar surface facets developing under electron irradiation. Attempts to understand the "dark-line" contrasts associated with the surface atom profiles, following comparison of the experimental images with computer modelling, leads to the realization that aluminium atom and oxygen atom surface terminations may be distinguished. Hence surface polarity, as well as details of surface step structure and mobility, may be determined. Positive surface polarity is preferred.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Atomic and Molecular Physics, and Optics