Detection of heat flux at single-atom scale in a liquid-solid interfacial region based on classical molecular dynamics

Abstract

In this study, we examine heat flux at the single-atom scale in a liquid-solid interfacial region by calculating local quantities based on classical molecular dynamics. The heat flux was calculated over a subatomic area defined on the liquid-solid interfacial region, and a two-dimensional map of the local heat flux at the liquid-solid interface was obtained. The results clearly showed directional heat flux at the single-atom scale between the liquid and solid phases; the spatial heat conduction was not uniform along a temperature gradient in the immediate vicinity of the solid surface, which suggests that the interfacial thermal resistance can be interpreted more precisely based on the local quantity of the heat flux. The methodology and results given in this study should prove useful to more precisely interpret and control heat transfer and thermal resistance at interfaces.