Free-electron lasers produce extremely brief, coherent, and bright laser-like photon pulses
that allow to image matter at atomic resolution and at timescales faster than the …

Excitons–two-particle correlated electron-hole pairs–are the dominant low-energy optical
excitation in the broad class of semiconductor materials, which range from classical silicon …

The interaction of intense particle bunches with plasma can give rise to plasma wakes,
capable of sustaining gigavolt-per-metre electric fields,, which are orders of magnitude …

Five years have now passed since the publication of the third edition of Principles of Free-
Electron Lasers and, while the field has matured considerably, we felt that there have been …

The conversion of photon energy into other energetic forms in molecules is accompanied by
charge moving on ultrafast timescales. We directly observe the charge motion at a specific …

Longitudinal electron-beam diagnostics play a critical role in the operation and control of x-
ray free-electron lasers, which rely on parameters such as the current profile, the …

A novel X-ray gas monitor (XGM) has been developed which allows the measurement of
absolute photon pulse energy and photon beam position at all existing and upcoming free …

The free-electron laser in Hamburg, FLASH, is the first extreme ultra-violet and soft X-ray
free-electron laser (FEL) user facility and has been continuously upgraded since its start in …

The non-monochromatic beamline BL1 at the FLASH free-electron laser facility at DESY was
upgraded with new transport and focusing optics, and a new permanent end-station, CAMP …

The successful realization of high gain free-electron lasers has opened new possibilities to
X-ray scientists for investigating matter in different states. The availability of unprecedented …