Our group supports pump lasers for use with experiments at SwissFEL.
The main mission of the pump laser group is to provide technical and scientific support for user experiments that use synchronized conventional pulsed lasers in combination with the SwissFEL free electron laser. We are responsible to maintaining and developing the pulsed laser systems that are delivered to the experiment stations. We also work closely together with the staff of the experiment stations to deliver a wide variety of pump capabilities for user experiments and photon diagnostics. We also provide limited emergency support of other laser systems connected to SwissFEL together with the gun laser group.
At present we have two Ti:Sapphire based laser systems installed at the SwissFEL with transport optics allowing delivery to the Alvra and Bernina enstations of ARAMIS. The lasers are both synchronized to the 100 Hz operation mode of ARAMIS. Each laser independently provides up to 10 mJ of energy per pulse for experiments at 800 nm center wavelength, with a pulse duration 35 fs RMS. The laser group also supports various schemes for converting the wavelength to other values, currently on a best-effort basis with no guarantee of minimum pulse energies or pulse durations. For both the Alvra and Bernina stations optical parameteric amplifiers (OPAs) in combination with nonlinear conversion modules can provide tuneable radiation from 240 nm to 2500 nm. At Bernina DFG modules exist to include the 2500 nm to 14 micron range. We are also able to employ optical rectification (OR) schemes to generate near-single-cycle THz-frequency pulses with center frequencies near 1 THz. Preliminary efforts have measured maximum THz fields > 300 kV/cm for such pulses when used in combination with he XFEL. Users interested in these options or others (e.g. narrow-band mid-IR pulses between 2.5 and 14 microns) are encouraged to contact the pump laser group or the appropriate endstation responsibles for discussions on what is feasible.