Topography and dynamics of surface defects on ionic crystals

Abstract

Scanning Force Microscopy (SFM) offers new possibilities for surface studies on insulators, but still needs work on interpretation of the images and on the limits of what may or may not be measured. Experimental and theoretical investigations of tip-sample interactions and interpretation of images at the atomic length scale are discussed. Observations have been made on pure crystals, samples doped with charged defects, and mixed crystal alloys. The SFM has proved useful in investigations of radiation damage on insulators at mesoscopic scales, using both ex situ and in situ irradiation.

Dynamical processes involving surface defects are an increasingly active area of investigation. Topics include energy transfer from self-trapped excitons to adsorbates or surface constituents and desorption mediated by surface defects.

Key Words:

• surface defects
• ionic crystals
• scanning force microscopy
• desorption