Berlin 2018 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

MM: Fachverband Metall- und Materialphysik

MM 47: Poster Session II

MM 47.16: Poster

Mittwoch, 14. März 2018, 18:30–19:45, Poster C

Molecular Dynamics Simulations of Laser Ablation in Covalent Materials — •Dominic Klein, Alexander Kiselev, and Johannes Roth — Institut für Funktionelle Materie und Quantentechnologien, Universität Stuttgart, Germany

Non-equilibrium phenomena in highly excited covalent systems induced by strong laser radiation fields have received much attention in recent years. Despite of many theoretical and computational investigations these ultra fast processes are still not well understood. Here we use multi-million particle molecular dynamics simulations to study the laser ablation in covalently bonded materials. A combined self-consistent continuum-atomistic model was applied for carrier-lattice interaction and electron-hole recombination processes. In addition, the temporal and spatial dependence of the exited carrier density was taken into account by fitting the inter atomic forces to finite-temperature density functional theory calculations.

Both, spatially homogeneous and Gaussian distributed laser power densities have been carried out. Furthermore, by using single-, double- and triple-pulse femtosecond laser irradiations it is demonstrated how the properties of the pulse sequence lead to drastic changes in bulk properties like the ablation threshold or the absorption length due to the time scale of free carriers relaxation.