Linear accelerator-based free-electron lasers (FELs) are the leading source of fully coherent
X-rays with ultra-high peak powers and ultra-short pulse lengths. Current X-ray FEL facilities …

Free-electron lasers and high-harmonic-generation table-top systems are new sources of
extreme-ultraviolet to hard X-ray photons, providing ultrashort pulses that are intense …

X-ray free-electron lasers (FELs) are state-of-the-art scientific tools capable to study matter
on the scale of atomic processes. Since the initial operation of X-ray FELs more than a …

A self-seeded X-ray free-electron laser (XFEL) is a promising approach to realize bright, fully
coherent free-electron laser (FEL) sources in the hard X-ray domain that have been a long …

High-resolution X-ray spectroscopy in the sub-nanosecond to femtosecond time range
requires ultrashort X-ray pulses and a spectral X-ray flux considerably larger than that …

Attosecond pulses are central to the investigation of valence-and core-electron dynamics on
their natural timescales,–. The reproducible generation and characterization of attosecond …

The Shanghai soft X-ray Free-Electron Laser facility (SXFEL), which is the first X-ray FEL
facility in China, is being constructed in two phases: the test facility (SXFEL-TF) and the user …

We demonstrate the generation of extreme-ultraviolet (XUV) free-electron laser (FEL) pulses
with time-dependent polarization. To achieve polarization modulation on a femtosecond …

The Shanghai High repetition rate XFEL and Extreme light facility (SHINE) is under
construction and aims at generating X-rays between 0.4 and 25 keV with three FEL …

It is a long-standing challenge for laser technologies to generate intense fully coherent
pulses in the x-ray regime. Here, we demonstrate an external seeding mechanism, termed …