STM Imaging of Single-Atom Adsorbates on Metals
Consider the imaging of a single atom adsorbed on a metal surface in the STM. Ideally, the STM tip will also be one atom adsorbed on a group of other metal atoms. For theoretical purposes, we will model this system using two flat metallic electrodes, each of which has a single atom adsorbed on its surface, with one representing the tip and the other the sample. If we calculate the current that flows between these electrodes when a bias voltage is applied between them, then we can study theoretically many of the basic physical aspects of STM imaging.
KeywordsDepression Helium Meso
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