A new scientific frontier opened in 2009 with the start of operations of the world's first x-ray
free-electron laser (FEL), the Linac Coherent Light Source (LCLS), at SLAC National …

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 …

Since the invention of the laser more than 50 years ago, scientists have striven to achieve
amplification on atomic transitions of increasingly shorter wavelength,,,,,,. The introduction of …

Diffraction-before-destruction imaging with ultrashort X-ray pulses can visualize non-
equilibrium processes, such as chemical reactions, with sub-femtosecond precision in the …

X-ray free-electron lasers (FELs) produce femtosecond x-ray pulses with unprecedented
intensities that are uniquely suited for studying many phenomena in atomic, molecular, and …

Quantum optics with X-rays has long been a somewhat exotic activity, but it is now rapidly
becoming relevant as precision x-ray optics and novel X-ray light sources, and high-intensity …

The ultrabright femtosecond X-ray pulses provided by X-ray free-electron lasers open
capabilities for studying the structure and dynamics of a wide variety of systems beyond …

X-ray scattering is typically used as a weak linear atomic-scale probe of matter. At high
intensities, such as produced at free-electron lasers, nonlinearities can become important …

Short-wavelength free-electron lasers are now well established as essential and unrivalled
sources of ultrabright coherent X-ray radiation. One of the key characteristics of these …

Excited double-core-hole states of isolated water molecules resulting from the sequential
absorption of two x-ray photons have been investigated. These states are formed through an …