Majed CHERGUI

Elettra Sincrotrone Trieste S.C.p.A., Strada Statale 14 - km 163,5, 34149 Basovizza, Trieste, Italy

and

Lausanne Centre for Ultrafast Science (LACUS), École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland

Emeritus Professor of the Ecole Polytechnique Fédérale de Lausanne in Switzerland and Group leader at Elettra-Sincrotrone Trieste in Italy, Majed Chergui is known for pioneering novel ultrafast spectroscopic methods for the study molecular systems, proteins and solids. In particular, he developed ultrafast X-ray spectroscopy, which has witnessed a huge growth with the advent of Free Electron Lasers. He was the founding director of the Lausanne Centre for Ultrafast Science (LACUS) and was the founding editor of the journal Structural Dynamics (AIP Publishing) between 2014 and 2020. In recognition of his achievements, he has received several Awards and Prizes, the most recent ones in 2026 being the Great Arab Minds award (UAE) and the Meggers award (Optica, USA).

Ultrafast science with optical and X-ray lasers

Ultrafast science has witnessed dramatic developments since its birth in the early 1990s.  One of these developments was the advent of X-ray Free Electron lasers (XFELs) around 2010. With ultrashort pulses, high photon flux/pulse, degree of coherence and photon energy range, these sources enable probing dynamics of matter at the atomic-scales of time (femtoseconds) and length (Ångströms). This is a game changer for describing photoinduced processes in (bio)chemical and material systems. A full description requires however input from optical domain (ultraviolet to infrared) experiments carried out with table-top lasers.

I will present examples of combining ultrafast optical domain and X-ray spectroscopic studies, showing some representative examples on (bio)chemical and material systems.

I will present recent developments that that aim at exploiting the high photon fluxes at XFELs in the emerging field of non-linear X-ray science.