Multiscale simulation of phonon transport in superlattices

A particle-based model for phonon transport and the scattering of phonon wave packets at interfaces is developed. The model, which incorporates the interference effects associated with the wave nature of phonons, is parametrized with frequency-dependent scattering rates obtained from molecular-dynamics simulations of the interaction of phonon wave packets with a single interface. From simulations of scattering of phonon wave packets from superlattices, we find that when the interference effects are not included there is qualitative disagreement between the molecular-dynamics and particle simulations. Moreover, we show that such interference effects tend to result in a larger amount of energy being transmitted through a superlattice.