Molecular Dynamics Simulations and Kaptiza Conductance Prediction of Si/Au Systems Using the New Full 2NN MEAM Si/Au Cross-Potential

Superlattices made by superposing dielectric and metal nanolayers are of great interest as their small size may increase the thermoelectric figure of merit. Thus it is essential to predict their thermal conductivity. Potentials for Au and Si are discussed and the potential of 2NN MEAM is chosen as being the best for simulating heat transfer in Si/Au systems. Full 2NN MEAM Si/Au cross-potential parametrization is developed and the results are compared with ab initio calculus to test its ability to reproduce local density approximation (LDA) calculations. NVT molecular dynamics simulations are performed to deposit Au atoms on an Si substrate by physical vapor deposition and the results of the intermixing zone are in good agreement with the Cahn and Hilliard theory. Non-equilibrium molecular dynamics simulations are performed for an average temperature of 300 K to determine the Kaptiza conductance of Si/Au systems, and the value of 188 MW/m²K obtained is in good agreement with the results of Komarov et al. for Au deposited on isotopically-pure Si-28 and natural Si, with values ranging between 133 and 182 MW/m²K.