Atoms and Molecules in the Focus of Intense Laser Pulses
PD Dr. Robert Moshammer
(Max-Planck-Institut für Kernphysik, Heidelberg)
28.10.2009
The ongoing achievements in the field short-pulse laser technology, the generation of extremely intense VUV-radiation with free-electron lasers (FEL) and, last but not least, the development of modern many-particle imaging spectrometers (so called ‘Reaction Microscopes’) offer new possibilities to study the dynamical behaviour of atoms and molecules in ultra-short (5 – 20 fs) and very intense (up to 1016 W/cm2) laser fields. Recent studies of the most basic atomic fragmentation reactions brought new insights, a couple of surprises and unexpected challenges to theory. In pump-probe experiments with small molecules the rotational and vibrational motion was followed in real-time and it is hoped that in near future even the formation of new bonds can be traced as function of time. In first experiments with VUV laser pulses at the FEL in Hamburg the simultaneous absorption of two or three photons has been studied, a regime that is completely unexplored up to now. It was found that the conformational and electronic structure of molecules can be explored in utmost detail with such intense VUV laser pulses. Presently, work is in progress to visualize, for the very first time, the breaking of chemical bonds as a function of time and, thus, to realize the dream of producing a “molecular movie”.