Temperature dependence of the optical excitation lifetime and band gap in chirality assigned semiconducting single-wall carbon nanotubes

The temperature dependence of optical excitation lifetime 1/Gamma and transition energies E(ii) were measured for bucky papers of single-wall carbon nanotubes (SWCNTs) and inner tubes in double-wall carbon nanotubes (DWCNTs) using resonant Raman scattering on the radial breathing mode. The temperature dependence of Gamma and E(ii) is the same for both types of samples and is independent of tube chirality. The data suggest that electron-phonon interaction is responsible for the temperature dependence of E(ii) and Gamma. The temperature independent contribution to Gamma is much larger in SWCNT than in DWCNT samples. This is explained by the different nanotube environment in the two types of samples. Gamma for the inner tubes of the DWCNTs is only similar to 30 meV below 150 K, which is comparable to that found for individual SWCNTs and is considered as intrinsic to the tubes.