Energy deposition models for short-pulse laser-solid interaction experiments

Abstract

Reliable models for the transport and deposition of energy in solid targets during short-pulse laser matter interactions are vital for designing and interpreting material properties experiments, and of clear relevance to the fast igniter. We conduct hybrid plasma simulations using LSP, considering relatively modest intensities to facilitate comparisons with radiation hydrodynamic models. The relative effects of thermal wave heating, direct collisional heating by fast electrons and Ohmic heating are discussed. Target heating depends strongly on the form of the hot electron distribution produced by the absorption of the incident laser pulse at the vacuum-matter interface. Where the hot electron population is assumed to be a discrete beam, we find good agreement with our models. For the case of a thermalised hot electron population, target heating by hot electrons is reduced. Under these conditions, the interplay between fast-electron and thermal wave heating is unclear, which has implications for target heating experiments.