Covalent and Reversible Short-Range Electrostatic Imaging in Noncontact Atomic Force Microscopy

Publisher Website
Google Scholar
Abstract
We present a computational study of atomic-scale image formation in noncontact atomic force microscopy on metallic surfaces. We find two imaging scenarios: (1) atomic resolution arising due to very strong covalent tip-sample interaction exhibiting striking similarity with the imaging mechanism found on semiconductor surfaces, and (2) a completely new mechanism, reversible short-range electrostatic imaging, arising due to subtle charge-transfer interactions. Contrary to the strong covalent-bond imaging, the newly identified mechanism causes only negligible surface perturbation and can account for results recently observed experimentally.