Molecular Dynamics of Diffusive-Ballistic Heat Conduction in Single-Walled Carbon Nanotubes

Diffusive-ballistic heat conduction of finite-length single-walled carbon nanotubes has been studied by means of non-equilibrium molecular dynamics simulations. The length-dependence of thermal conductivity is quantified for a range of nanotube-lengths up to a micrometer at room temperature. A gradual transition from nearly pure ballistic to diffusive-ballistic heat conduction was identified from the thermal conductivity profile. In the diffusive-ballistic regime, the profile exhibits power-law length dependence and does not converge even with the tube-length of a micrometer. Furthermore, the diameter dependence of thermal conductivity suggests considerable suppression of phonon scattering effect as the diameter decreases.