A Molecular Dynamics Simulation of Heat Conduction in Finite Length SWNTs

The heat conduction in finite length single walled carbon nanotubes (SWNTs) was simulated by the molecular dynamics method with the Tersoff-Brenner bond order potential. Temperature at each end of a SWNT was controlled by the phantom technique, and the thermal conductivity was calculated from the measured temperature gradient and the energy budgets in phantom molecules. The thermal conductivity was measured for (5,5) and (10,10) SWNTs with various lengths from 6 nm through 404 nm. Measured thermal conductivity for smaller diameter (5,5) nanotube did not converge to a finite value with increase in tube length, but obeyed a striking power law relation. The phonon density of states and phonon dispersion relations were calculated from the simulated results for the better understanding of the heat conduction mechanism.