Numerical analysis of nanocluster formation within ns-laser ablation plume

Abstract

The CIP method is used to calculate macroscopic plume expansion combined with the Zeldovich–Raiser theory for the cluster-formation process such as nucleation and growth. The effect of background gas and latent heat is examined in the one-dimensional case. The latent heats keep the plume temperature at 2500 K for a long period and this explains the delayed photoluminescence. Two contradicting experiments on the size dependence on ambient pressure are clearly explained and are attributed to the difference of laser energy. In two-dimensional simulation, a ‘mushroom-like’ plume shape is replicated, consistent with experimental results.