Advances in single nanotube spectroscopy: Raman spectra from cross-polarized light and chirality dependence of Raman frequencies Original Research Article

This work discusses new results obtained from analysis of Raman signal from isolated single wall carbon nanotubes. (1) Study of tangential (G band) modes frequency dependence on tube diameter and lineshape dependence on scattering polarization geometry shows clear observation of symmetry selection rules at the single nanotube level. Observation of E2 phonon modes indicates Raman spectra coming from cross-polarized light, i.e. from Eμv→Eμ±1c electronic transitions. (2) Study of the disorder induced (D) band and other small intensity features show strong dependence of Raman frequencies of nanotube chiral angle.