Short-pulse laser radiation focused on the surface of a material can simultaneously cause a large number of interconnected nonequilibrium processes that occur in a submicron interval within several picoseconds. Under the implemented extremal conditions, the ablation mechanism induced in a solid substance is extremely complex and has elicited numerous contradictory interpretations. A possible way to investigate its mechanism under strong nonequilibrium conditions is by using molecular dynamics. This method is used in this paper as a basis for a hybrid atomistically continuous model to describe how a picosecond laser pulse interacts with single-crystal and polycrystalline targets made from gold. The kinetics and the mechanism of induced ablation are studied. Differences are detected, and their causes are determined.
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