Optical transition energies for carbon nanotubes from resonant Raman spectroscopy: Environment and temperature effects

• Published in: Physical review letters 2004-10, Vol.93 (14), p.147406.1-147406.4, Article 147406
• Main Authors: FANTINI, C, JORIO, A, SOUZA, M, STRANO, M. S, DRESSELHAUS, M. S, PIMENTA, M. A
• Format: Article
• Language: English
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Environment; Exact sciences and technology; Nanotubes; Nanotubes, Carbon - chemistry; Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation; Optical properties of low-dimensional, mesoscopic, and nanoscale materials and structures; Physics; Spectrum Analysis, Raman - methods; Temperature
• ISSN: 0031-9007; 1079-7114
• DOI: 10.1103/physrevlett.93.147406

This Letter reports the laser energy dependence of the Stokes and anti-Stokes Raman spectra of carbon nanotubes dispersed in aqueous solution and within solid bundles, in the energy range 1.52-2.71 eV. The electronic transition energies (E(ii)) and the radial breathing mode frequencies (omega(RBM)) are obtained for 46 different (18 metallic and 28 semiconducting) nanotubes, and the (n,m) assignment is discussed based on the observation of geometrical patterns for E(ii) versus omega(RBM) graphs. Only the low energy component of the E(M)(11) value is observed from each metallic nanotube. For a given nanotube, the resonant window is broadened and down-shifted for single wall carbon nanotube (SWNT) bundles compared to SWNTs in solution, while by increasing the temperature, the E(S)(22) energies are redshifted for S1 [(2n+m) mod 3=1] nanotubes and blueshifted for S2 [(2n+m) mod 3=2] nanotubes.