Domain size effects in molecular dynamics simulation of phonon transport in silicon

Molecular dynamics (MD) simulation is employed to compute thermal conductivity and dispersion curves for bulk silicon using the environment dependent interatomic potential. Thermal conductivity simulations using the Green-Kubo method are found to converge to the bulk value with 216 atoms or more. Computed values in the 300–1000K range compare well with experiment. MD results are analyzed to obtain phonon dispersion curves along the [100] direction and compare well with those using the dynamical matrix approach. It is found that bulk thermal properties may be computed using MD in relatively small domains provided that the dominant energy-containing wavelengths are well resolved.