A new concept for the SwissFEL laser based on a hybrid Ytterbium oscillator and amplifier was presented at the Free Electron Laser Conference in late August by a team from Paul Scherrer Institute and France-based ultrafast laser maker Amplitude Systèmes. The SwissFEL x-ray laser, the next large-scale facility at Paul Scherrer Institute (PSI), is now under construction and scheduled to go online in 2016. It will produce very short pulses of x-ray light with laserlike properties. Such light will be used to visualize extremely fast processes, including how new molecules are created in a chemical reaction and how vital biological molecules assemble. Knowledge gained from experiments there could lead to the creation of new drugs, more efficient processes in the chemical industry, new materials for electronics and alternative processes in energy production. Outline of the SwissFEL being built at PSI. The upper part is a sketch of the total length of the SwissFEL broken up in injector and the three linac components, and the lower part is a more detailed view of the experimental site, including undulator and experimental setup for the soft (ATHOS) and the hard (ARAMIS) x-ray beamlines. Courtesy PSI. Most FEL facilities use laser systems based on titanium:sapphire technology, but the new system consists of a hybrid ytterbium (Yb) fiber and solid-state Yb:CaF2 amplifier. The prototype laser tested at Amplitude Systèmes. The various stages are packaged in sealed, temperature-stabilized boxes. The laser's performance — energy stability, timing jitter, double pulse operation, temporal and spatial pulse shape of the ultraviolet pulses — matches SwissFEL requirements, the partners say. The mature and stable, direct-diode pumping technology and an optimized design allow for high reliability, long lifetime and lower maintenance cost compared with the widely used Ti:sapphire laser systems, they claim. The 35th International Free-Electron Laser Conference, organized by Brookhaven National Laboratory, was held Aug. 25-30 in Manhattan. For more information, visit: www.psi.ch/media/overview-swissfel or www.c-ad.bnl.gov/fel2013.