Resonant Raman Spectroscopy of Armchair Carbon Nanotubes: Absence of "Metallic" Signature

Abstract

The appearance of a broad peak at $\sim$1550 cm${}^{-1}$ (G${}^{-}$ peak) in carbon nanotube resonant Raman scattering spectra has been conventionally attributed to the presence of metallic nanotubes. Here, we present resonant Raman measurements on macroscopic nanotube ensembles enriched in armchair species prepared through density gradient ultracentrifugation. Our data clearly demonstrate that the broad G${}^{-}$ mode is absent for armchair structures and appears only when the excitation laser is resonant with non-armchair "metals." Due to the large number ($\sim$10${}^{10}$) of nanotubes across several armchair species probed, our work firmly establishes a general correlation between G-band lineshape and nanotube structure.

4 pages, 4 figures

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Cited by in corpus (4)

• Terahertz Science and Technology of Carbon Nanomaterials
• Fundamental Optical Processes in Armchair Carbon Nanotubes
• Coherent Phonons in Carbon Nanotubes and Graphene
• Ultrafast Generation of Fundamental and Multiple-order Phonon Excitations in Highly-Enriched (6,5) Single-Wall Carbon Nanotubes