Effect of substrate on thermal conductivity of single-walled carbon nanotubes

We analyze numerically the thermal conductivity of single-walled carbon nanotubes placed on a flat rigid substrate. We demonstrate that the character of thermal conductivity depends crucially on the interaction between the nanotube and the substrate. In particular, we reveal that unlike the well-established anomalous thermal conductivity of isolated carbon nanotubes, the nanotube placed on a substrate demonstrates normal thermal conductivity due to the appearance of a narrow gap in the frequency spectrum of acoustic phonons.