%0 Journal Article %A A L Moore %A S K Saha %A Ravi S Prasher %A L Shi %B Appl. Phys. Lett. %D 2008 %G eng %I aip.scitation.org %R 10.1063/1.2970044 %T Phonon backscattering and thermal conductivity suppression in sawtooth nanowires %8 08/2008 %X

The effect of surface roughness on phonon transport in a nanowire has often been described by treating the surface as flat with a specularity parameter $(p)$ in the range between 0 and 1. A lower thermal conductivity limit is approached at $p = 0$ for diffuse surface. It is demonstrated here by Monte Carlo simulation that sawtooth roughness on a nanowire can cause phonon backscattering and suppress the thermal conductivity below the diffuse surface limit. The backscattering effect can be accounted for only by a negative $p$ if the detail of the surface roughness is ignored.