The Orsay Infrared Laser Center (CLIO) is an infrared host centre based on a free electron laser (FEL). It is one of the two research accelerators of the Laboratory of Physical Chemistry (LCP), with ELYSE. Since its inauguration in 1991, CLIO is actively involved in French, European and international research. It is one of three infrared-tunable European free-electron lasers that are opened to the scientific community. The center also includes experimental platforms open to users: In addition to the LEL, each platform is equipped with tunable nanosecond or picosecond pulsed lasers that allow autonomous work in the near and medium infrared and in the visible range. 4000 hours of beam offered to users (35 to 40 weeks per year) 12 to 15 partner countries for 25 to 40 scientific projects per year 20 to 30 publications per year

The ELBE Center for High-Power Radiation Sources at HZDR is open to users providing ultrashort pulses of intense THz and IR radiation at high repetition rates (up to 13 MHz). The two free-electron lasers of FELBE cover the mid- and far-infrared spectral range from 5 – 250 µm and the superradiant THz sources of TELBE cover a spectral range of 0.1 – 2.5 THz.

The 3.4 km long European XFEL generates extremely intense X-ray flashes to be used by researchers from all over the world. The flashes are produced in underground tunnels and will allow scientists to map atomic details of viruses, film chemical reactions, and study the processes in the interior of planets.

The FELIX Laboratory at Radboud University (Nijmegen, the Netherlands) exploits intense, short-pulsed infrared and THz free electron lasers that are used for research of matter both by in-house as well as national and international external users. The four lasers FELIX-1, FELIX-2, FELICE and FLARE each produce their own range of wavelengths and together, they provide a tuning range between 3 and 1500 µm.

FERMI (acronym for Free Electron laser Radiation for Multidisciplinary Investigations) is the new seeded free electron laser (FEL) facility under commissioning with external users next to the third-generation synchrotron radiation facility Elettra. Unique among the FEL sources currently operating in the ultraviolet and soft x-ray range worldwide, FERMI has been developed to provide fully coherent ultrashort (10-100 femtosecond) pulses with a peak brightness ten billion times higher than that made available by third-generation light sources. FERMI is opening unique opportunities for exploring the structure and transient states of condensed matter, soft matter and low-density matter using a variety of diffraction, scattering and spectroscopy techniques.

The two FLASH experimental halls "Kai Siegbahn" (left) and "Albert Einstein" (right) are located between the PETRA III experimental halls.

TheSwissFEL is based on a novel technology holding exceptional promises for diverse areas of scientific research. Serving our society's modern trends "smaller, faster, more complex", SwissFEL will provide unprecedented insights into structures as small as an atom and into phenomena as fast as the vibrations of molecular bonds. It will also reveal the secrets behind the inner complexity of technologically relevant materials

Fully operational TARLA will provide FEL with resonant wavelengths of 5-350 µm at a repetition rate of 13 MHz and the pulse duration of 1-10 ps. This type of beam which covers the mid to far-infrared spectral range is expected to have an average power in 0.1 - 100 W range.