LIGHT-MATTER INTERACTION ON ULTRASHORT TIME SCALES

Recent advances in ultrafast optics have permitted the realization of ultrashort, high-intensity laser systems and of ultrashort coherent x-ray sources. These radiation sources are unique in several respects and open the possibility to investigate light matter interaction on a novel time scale and in unprecedented wavelength and intensity regimes. In the wake of the rapid development of pulsed radiation sources a wealth of applications will become possible affecting a broad range of research areas: To mention a few of them: coherent xuv radiation sources will benefit semiconductor industry (nanolithography), medicine (x-ray diagnostics) and life sciences (cell biology); x-ray pulses will make the study of fundamental processes with unprecedented accuracy possible, such as the making and breaking of chemical bonds. The experimental progress has posed new theoretical. challenges. In order to realize the ambitious applications brought up above, a thorough understanding of the physical processes taking place in the new parameter regimes of electromagnetic radiation-matter interaction is necessary. This is the goal of the current project. Influence of the proposed work on the development of the field Presumably, only a few of the many implications resulting from our work can be assessed at the present time. Our investigations suggest that phase controlled light pulses will allow precise control of high-intensity light matter interaction on a sub-cycle time scale. Consequences include the generation of a single x-ray burst of less than 100 attoseconds in duration. These pulse durations approach the atomic time scale and will allow tracing quantum dynamics of electrons in atoms and the investigation of electron correlation effects. Laser driven acceleration in plasmas could make sub-100fs x-ray generation possible. The search of laser-driven ultrafast sources is motivated by a number of important processes in the microscopic world. Sub-100fs x-ray pulses will allow tracing nuclear motion in a wide range of phenomena including phase transitions in the solid phase, and the formation and breaking of chemical bonds by time resolved x-ray diffraction.