Molecular Dynamics Simulation of Thermal Conductivity of Nanocrystalline Composite Films

The effectiveness of a thermoelectric device is measured by the figure of merit ZT, which is inversely proportional to the thermal conductivity. Superlattice materials often have a reduced thermal conductivity because of the introduction of interface scattering and, therfore, improved performance. The present work is focused on the effective thermal conductivity of nanocomposite films. This configuration could also improve ZT because of phonon-interface scattering introduced by the nanocrystals. The effects of crystal size and mass fraction is studied numerically using a molecular dynamics simulation. Results indicate that a reduction in the effective thermal conductivity can be achieved with the addition of a nanocrystal.