One-dimensional energy dispersion of single-walled carbon nanotubes by resonant electron scattering.

We characterized the energy band dispersion near the Fermi level in single-walled carbon nanotubes using low-temperature scanning tunneling microscopy. Analysis of energy-dependent standing wave oscillations, which result from quantum interference of electrons resonantly scattered by defects, yields a linear energy dispersion near E(F), and indicates the importance of parity in scattering for armchair single-walled carbon nanotubes. Additionally, these data provide values of the tight-binding overlap integral and Fermi wave vector, in good agreement with previous work, but indicate that the electron coherence length is substantially shortened.