Raman excitation profiles for single wall carbon nanotubes

Abstract

The Raman excitation profiles for single wall carbon nanotubes with diameter range 8-20 Å are calculated using transition probability in the third order perturbation theory and full symmetry of nanotubes. Due to the strong antenna effect, only incoming and scattered light polarized along the tube axis is considered. In such a geometry only the totaly symmetric, radial breathing (being the main scope of the paper) and high energy phonon modes are Raman active. Strong dependence of resonant maxima on tube parameters is found. Absence of the second transition peak in excitation profiles of semimetallic tubes is explained as a consequence of weak electron-phonon coupling. © 2007 American Institute of Physics.