Stefan Düsterer

TL;DR: In this paper, the performance of a free-electron laser operating at a wavelength of 13.7 nm where unprecedented peak and average powers for a coherent extreme-ultraviolet radiation source have been measured.

TL;DR: In this paper, the FLASH soft X-ray free-electron laser was used to reconstruct a coherent diffraction pattern from a nano-structured nonperiodic object, before destroying it at 60,000 K.

TL;DR: Using coherent diffraction imaging with femtosecond X-ray free-electron-laser pulses, this paper captured time-series snapshots of a solid as it evolves on the ultrafast timescale.

TL;DR: This work uses femtosecond X-ray pulses from a free-electron laser to study thin film samples with magnetic domain patterns and observes an infrared-pump-induced change of the spin structure within the domain walls on the sub-picosecond timescale, demonstrating the importance of spin-dependent electron transport between differently magnetized regions as an ultrafast demagnetization channel.

TL;DR: A general numerical approach is described that allows obtaining model sets of temporal pulse shapes of free-electron lasers operating in the self-amplified spontaneous emission mode that satisfy statistical criteria of FEL light predicted by established FEL theory.