We analyze the defect-induced Raman mode (D mode) and the second order 2D mode of samples enriched with metallic and semiconducting single-walled carbon nanotube (SWCNT). By resonance Raman spectroscopy, we study the evolution of the line shape of the D and 2D mode. We compared the radial-breathing mode (RBM) frequencies with different components of the D and 2D mode in the enriched samples and a non-enriched SWCNT reference material. We show that the components of the broad D mode can be assigned to different species of nanotubes and that this assignment is not necessarily correlated to the RBM for the same excitation energy.
Raman intensity of the 2D mode for differently enriched samples and comparison with a reference sample. The gray spectrum is the sum of the spectra from the enriched samples.