Picosecond pump–probe X‐ray scattering at the Elettra SAXS beamline.

A new setup for picosecond pump–probe X‐ray scattering at the Austrian SAXS beamline at Elettra‐Sincrotrone Trieste is presented. A high‐power/high‐repetion‐rate laser has been installed on‐site, delivering UV/VIS/IR femtosecond‐pulses in‐sync with the storage ring. Data acquisition is achieved by gating a multi‐panel detector, capable of discriminating the single X‐ray pulse in the dark‐gap of the Elettra hybrid filling mode. Specific aspects of laser‐ and detection‐synchronization, on‐line beam steering as well protocols for spatial and temporal overlap of laser and X‐ray beam are also described. The capabilities of the setup are demonstrated by studying transient heat‐transfer in an In/Al/GaAs superlattice structure and results are confirmed by theoretical calculations. [ABSTRACT FROM AUTHOR]