Dephasing of G-Band Phonons in Single-Wall Carbon Nanotubes Probed via   Impulsive Stimulated Raman Scattering
  We have studied the coherent dynamics of G-band phonons in single-walled carbon nanotubes through impulsive stimulated Stokes and anti-Stokes Raman scattering. The probe energy dependence of phonon amplitude as well as preferential occurrence between Stokes and anti-Stokes components in response to chirped-pulse excitation are well explained within our model. The temperature dependence of the observed dephasing rate clearly exhibits a thermally-activated component, with an activation energy that coincides with the frequency of the radial breathing mode (RBM). This fact provides a clear picture for the dephasing of optical phonons by random frequency modulation via interaction with the RBM through anharmonicity. 
J.-H. Kim, K.-J. Yee, Y.-S. Lim, L. G. Booshehri, E. H. Haroz, J. Kono
cond-mat.mes-hall cond-mat.mtrl-sci