Phonon Transport in Molecular Dynamics Simulations: Formulation and Thermal Conductivity Prediction

Publisher Summary This chapter discusses the phonon transport in molecular dynamics (MD) simulations. The chapter presents a formulation for studying the thermal transport in dielectric materials using MD simulations. The simulations allow for analysis in both the real and phonon spaces. The natural inclusion of anharmonic effects through the form of the interatomic potential presents a significant advantage over harmonic theories. The chapter describes, examines, and compares two major approaches for predicting thermal conductivity from MD simulations (the Green–Kubo method [GK] and direct methods). Each has advantages and disadvantages, and the method chosen strongly depends on the problem of interest. Generally, the GK method is superior for bulk phase simulations, while the direct method is best for finite structures. In terms of applying MD simulations to real systems, current computational resources cannot accurately model anything close to a micron in size on an atom-by-atom level. The upscaling of MD results to larger length scale models is a promising and exciting avenue. Upscaling has been applied in a different context to phonon transport across material interfaces by Schelling and Phillpot.