Vendredi 2 octobre 2026 à 11h00, salle 357 - IUSTI
Abstract: Ultrashort and high-power laser systems have taken a rapid development in the last decades, which has been also appreciated by several Nobel’s prices in the last years. Due to the delivered ultrashort pulse duration, the intensity of the focused light can be huge. This offers a lot of opportunities, in particular, for light-matter interaction. First, we concentrate on laser-plasma generation, matter at extreme conditions and the emission of high-energy particles (electrons & ions). Those plasmas may also act as unique bright sources of ultrashort pulses at very short wavelengths (XUV & X-ray). This, in particular, is the case for coherent high-order harmonics that are generated at the surface of dense plasmas. The second part of the talk shows that femtosecond laser plasmas may be used as ultrafast optical gates. These could be applied for the characterization of fs-pulses from the optical to the X-ray range (temporal evolution, timing etc.). We have set up such gates to characterize fs-XUV- and X- ray pulses of free electron lasers (FERMI, SLAC/LCLS, FLASH). Further experiments are related to the ultrafast graphitisation of diamond. The third part presents a few examples on laser micro machining, such as fs-laser ablation (e.g., for the improvement of the coupling efficiency of solar cells) and laser material modification (for optical wave guide generation). In the forth part we will discuss physics of shock waves at micro scale, a novel topic (fundamental research). Such waves can be generated by short laser pulses in fluid-filled capillaries. Most recent experiments have concentrated on the head on collision of micro shock waves, the very first and only experiments performed so far.
Ulrich Teubner — ILO, Univ. Applied Sciences Emden & Univ. Oldenburg