STM studies of single-walled carbon nanotubes

This topical review summarizes scanning tunneling microscopy investigations of the electronic properties of single-walled carbon nanotubes (SWNTs). First, the unique relationship between the atomic structurè and electronic properties of SWNTs is reviewed. Second, the one-dimensional electronic band structure of SWNTs is introduced, and a comparison of tunneling spectroscopy to tight-binding calculations is presented. Third, localized structures in nanotubes, such as intramolecular junctions and ends, are addressed. Fourth, quantum size effects in SWNTs are discussed. Lastly, the effects of external perturbations, specifically magnetic impurities, on the low energy properties of metallic SWNTs are discussed. Prospects for future research directions are considered.