Scanning tunneling microscopy of carbon nanotubes: simulation and interpretation

Scanning tunneling microscopy (STM) and scanning tunneling spectroscopy (STS) are powerful techniques to investigate electronic and topographical properties of carbon nanotubes. The growing availability of experimental data enables us to study perfect tubules and to probe particular features of nanotubes such as topological (twists) or non-topological (pentagonal and heptagonal rings) modifications of the hexagonal lattice and ending caps structures. We have recently proposed a general approach to interpret and predict STM and STS observations. Our formalism, which is based on a tight-binding framework, is sufficiently precise to be used routinely for various carbon sp(2) geometries. Confronted with experimental results, our approach reveals to be a useful tool to help in the interpretation and prediction of STM and STS measurements.