Molecular-dynamics simulation of thermal conductivity in amorphous silicon

The temperature-dependent thermal conductivity {κ}(T) of amorphous silicon has been calculated from equilibrium molecular-dynamics simulations using the time correlations of the heat flux operator in which anharmonicity is explicitly incorporated. The Stillinger-Weber two- and three-body Si potential and the Wooten-Weaire-Winer a-Si model were utilized. The calculations correctly predict an increasing thermal conductivity at low temperatures (below 400 K). The {κ}(T), for T>400 K, is affected by the thermally generated coordination-defect states. Comparisons to both experiment and previous calculations will be described.