Molecular Dynamics Prediction of Thermal Conductivity of GaN Films and Wires at Realistic Length Scales

Abstract

Recent molecular dynamics simulation methods have enabled thermal conductivity of bulk materials to be estimated. In these simulations, periodic boundary conditions are used to extend the system dimensions to the thermodynamic limit. Such a strategy cannot be used for nanostructures with finite dimensions which are typically much larger than it is possible to simulate directly. To bridge the length scales between the simulated and the actual nanostructures, we perform large-scale molecular dynamics calculations of thermal conductivities at different system dimensions to examine a recently developed conductivity vs. dimension scaling theory for both film and wire configurations. We demonstrate that by an appropriate application of the scaling law, reliable interpolations can be used to accurately predict thermal conductivity of films and wires as a function of film thickness or wire radius at realistic length scales from molecular dynamics simulations. We apply this method to predict thermal conductivities for GaN wurtzite nanostructures.

References in corpus (3)

• Towards More Accurate Molecular Dynamics Calculation of Thermal Conductivity. Case Study: GaN Bulk Crystals
• Heat capacity and phonon mean free path of wurtzite GaN
• An analytical law for size effects on thermal conductivity of nanostructures

Cited by in corpus (4)

• Effects of Cutoff Functions of Tersoff Potentials on Molecular Dynamics Simulations of Thermal Transport
• Effects of nano-void density, size, and spatial population on thermal conductivity: a case study of GaN crystal
• Recent Progress in the Concurrent Atomistic-Continuum (CAC) Method and its Application in Phonon Transport
• Size and Stoichiometric Dependence of Thermal Conductivities of InxGa1-xN: A Molecular Dynamics Study