Generation of nanoparticles by laser ablation: Combined MD-DSMC computational study

The early stage of the ablation plume formation and the following dynamics of the plume expansion are studied numerically using a combination of molecular dynamics and the direct simulation Monte Carlo methods. The direct cluster ejection from the target and the following cluster-monomer and cluster-cluster collisions are considered. The presence of the ablated clusters is shown to strongly affect the dynamics of the plume expansion, leading to considerable modifications of the plume structure. Plume segregation into two components observed in the simulations is in a good qualitative agreement with the results of recent plume emission measurements.