Significant advances with unconventional extreme ultraviolet (EUV) and soft x-ray spectroscopies have been recently achieved at the FERMI free electron laser in Trieste (Italy). Time-resolved x-ray absorption spectroscopy (tr-XAS) has been used to explore the sub-picosecond structural and electronic rearrangement in materials under extreme conditions of pressure and temperature driven by intense fs-laser pulses.
tr-XAS has been found to be effective also for monitoring the ultrafast charge transfer in photo-excited functional materials. Moreover, it has been successfully employed in combination with impulsive stimulated Raman scattering for revealing the molecular motion in real time with unprecedented elemental and enantiomeric selectivity.
High sensitivity to the atomic structure of interfaces in materials has been demonstrated by nonlinear second harmonic spectroscopy in the EUV range[4,5].
This seminar provides an overview on these disruptive experiments carried out at the beamline TIMEX of FERMI, outlining possible challenging developments and future opportunities for scientific research.
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