Probing the Intrinsic Vibrational and Optical Properties of Individual Chirality-Identified Carbon Nanotubes by Raman Spectroscopy
Résumé
The goal of this chapter is to review the main information derived from Raman spectroscopy on individual suspended (free-standing) chiralityidentified single-wall carbon nanotubes (SWCNTs) and double-wall carbon
nanotubes (DWCNTs) with a special focus on the characteristics of their radial breathing modes and G modes, including their resonance conditions. For
SWCNTs, the different relationships between the radial breathing mode frequency and the inverse of the diameter illustrate the high sensitivity of individual suspended SWCNTs to their environmental conditions. The intrinsic
profiles of the optical longitudinal (LO) and transverse (TO) G modes are unambiguously identified both for metallic and semiconducting chiral and achiral SWCNTs, and the diameter dependence of the LO and TO frequencies are established. In DWCNTs, the intertube coupling, originating from the van der Waals interaction between the inner and outer tubes, plays an important role in determining the features/characteristics of the collective
radial breathing-like modes and G modes.