Two-Temperature Non-Equilibrium Molecular Dynamics Simulation of Thermal Transport Across Metal-Nonmetal Interfaces

We have developed a two-temperature non-equilibrium molecular dynamics method for modeling interfacial thermal resistance across metal-nonmetal interfaces. Non-equilibrium molecular dynamics is used, where a temperature bias is imposed and the heat current is derived. On the metal side, the electron degree of freedom is added, and the electron-phonon coupling is treated with the two-temperature model. Temperature non-equilibrium between electrons and phonons in the metal side is quantitatively predicted, and a temperature drop across the interface is observed. The results agree with experimental data better than those obtained from conventional molecular dynamics simulations, which are only able to model phonons. Our method is capable of taking into account both electron and lattice degrees of freedom in a single molecular dynamics simulation, and is a generally useful tool for predicting metal-nonmetal interfaces.