Atomic-level Sharpening of a Carbon Nanotube Tip for High-resolution Scanning Tunneling Microscopy

Abstract

Using a multi-walled carbon nanotube (MW-CNT) tip, we have observed the honeycomb lattice of highly oriented pyrolytic graphite (HOPG) via scanning tunneling microscopy (STM). This observation was made after acquiring typical STM images of HOPG, i.e., showing the triangular lattice. We consider this change is due to atomic reconfiguration at the apex of the MW-CNT tip induced by continuous STM scanning. The atomic-level sharpening of CNT tips will be useful to image samples with small lattice constants or to obtain orbital information from samples with an orbital ordering such as manganites.