Quantum dephasing in carbon nanotubes due to electron-phonon coupling

We report on the effect of electron-phonon coupling on quantum transport in carbon nanotubes. The vibrational atomic displacements as well as the electron-phonon coupling strength are introduced through a time-dependent perturbation of the pi-electron Hamiltonian. The effect of dephasing on the Kubo conductance is studied for metallic and semiconducting nanotubes, and from a phenomenological law, coherence length (time) scales are found to fluctuate within the range 10 to 150 nm (0.01 to 4 ps) depending on the energy of charge carriers and phonon amplitude.