Using the Elettra storage-ring free-electron laser, we have implemented a light source
generating sub-picosecond (ps) coherent optical pulses in the VUV spectral range. The setup
relies on the frequency up-conversion of a high-power external signal (provided by a
Ti:Sapphire laser) and makes use of a relativistic electron bunch as resonating medium. The
produced VUV pulses have peak power in MW range, variable polarization, high shot-toshot
stability and control of the timing parameters at the ps level. In this paper, we present
the experimental layout, as well as the characterization of the temporal and spectral features
of the emitted light. The radiation can be exploited for new experiments in the fields of
dynamical phenomena, non-linear physics, magnetism and biology.
