报告题目：Thermal Conductivity of Monolayer Silicene

报 告 人：鲍华，上海交通大学密西根学院

报告时间：2015年3月24日10：00

报告地点：理科楼三楼报告厅（C302）

报告摘要：Silicene, as a graphene-like two-dimensional material, now receives exceptional attention of a wide community of scientists and engineers beyond graphene. Despite extensive study on its electric property, little research has been done to accurately calculate the phonon transport of silicene. In this work, we first optimized the Stillinger-Weber potential parameters specifically for a single-layer Si sheet, which can accurately reproduce the low buckling structure of silicene and the full phonon dispersion curves obtained from ab initio calculations. By performing equilibrium and nonequilibrium molecular dynamics simulations and anharmonic lattice dynamics calculations, we show that the three methods consistently yield a low thermal conductivity. We then use a more accurate first-principles based anharmonic lattice dynamics method to predict silicene thermal conductivity. Different methods show that the out-of-plane vibrational modes contribute less than 10% of the total thermal conductivity, which is fundamentally different from graphene. The difference is explained by the presence of small buckling, which breaks the reflectional symmetry of the silicene structure.