Temperature-dependent carrier dynamics in metallic carbon nanotubes

The low energy states in metallic armchair carbon nanotubes can decay by the electron-electron Coulomb interactions with the intraband and the interband excitations. The inelastic scattering rate is very sensitive to the changes in the electronic distribution and the state energy (or the wavevector). The temperature dependence is linear for the Fermi-momentum state. Such dependence is hardly affected by the nanotube radius and the Fermi energy. The electron-electron interactions are more efficient in electronic deexcitations compared with the electron-phonon interactions. The calculated results are roughly consistent with the experimental measurements from the time-resolved photoemission spectroscopy.