Étude théorique d'agrégats soumis à des champs laser intenses

During this PhD thesis we have been studying by two models the interaction of lasers (intensity 10^11 to 10^17 W/cm^2) with big size clusters (100 atoms to a few thousand).<br /> <br />We propose to add a term of damping with the surface to the original nanoplasma model of T.Ditmire et al. (1996). We get good agreement with experimental evidences (xenon) and study the evolution of charge states with size or intensity.<br /> <br />We propose a robust, three dimensional and microscopic, molecular dynamics model, stable in the absence of excitation. The soft Coulomb potential is parameterized to mimic the atomic energy levels. The electronic emission at 10^11 W/cm^2 (sodium) is comparable to the one obtained by other models such as VUU-LDA model. Core electrons are emitted from 5 10^15 W/cm^2. We show that rare events are accessible and that ionic explosion is Coulomb like and self-similar (10^16 W/cm^2). Eventually, electronic emission (rare gaz) is compared with the nanoplasma model.