It is with great sadness that we learned of the passing of our friend and colleague, Mehdi Zeghal, a lecturer and researcher at the Solid State Physics Laboratory (LPS) at Université Paris-Saclay. He fought with great courage against a long and terrible illness. We will always remember his humor, his generosity, his dedication to teaching and research, his genuine interest in others—colleagues and students alike—and his extensive general knowledge, which he loved to share over coffee in lively discussions punctuated by bursts of laughter.
Mehdi joined the LPS to pursue his doctorate under the supervision of Bertrand Deloche, working on the dynamics and ordering of polydimethylsiloxane layers grafted onto solid substrates using deuterium NMR. After a postdoctoral fellowship at the Léon Brillouin Laboratory, he joined the LPS in 1999 as a lecturer-researcher, first in the Organized Molecular Systems group and later in the Matter and Radiation group from 2012 onward. Mehdi’s main research interests focused on the structure and dynamics of polymers and complex polyelectrolytes, combining X-ray and neutron scattering approaches with NMR spectroscopy. He was deeply involved in the development and use of field-gradient NMR, which enables the measurement of molecular, macromolecular, and assembly dynamics over an extended time window, ranging from a few hundred microseconds to several tens of seconds.
Mehdi devoted himself wholeheartedly to physics education at Université Paris-Saclay. He was a driving force behind the Condensed Matter and Materials Platform, whose objective is to provide physics and chemistry students, including engineering students, with access to NMR spectrometers and X-ray generators similar to those used in research laboratories. He was regularly involved in supervising original experimental projects that illustrated the complementarity between teaching and research. In doing so, he often faced administrative and managerial challenges, and the community will always remember his strong commitment to this endeavor. Mehdi worked tirelessly to share his enthusiasm for science with students, always keeping their future and well-being in mind—an approach that was deeply appreciated.
Thanks to his extensive scientific knowledge, Mehdi was constantly full of ideas and engaged in stimulating discussions that helped advance a wide range of scientific projects related to his three main areas of expertise: polymers, NMR spectroscopy, and radiation scattering, with a particular interest in neutrons. Many of us benefited from this through lasting collaborations on demanding and innovative projects.
Beyond his professional life, his colleagues and friends appreciated his open-mindedness and broad culture. He enjoyed initiating discussions on eclectic and sometimes controversial topics, drawing on his bicultural background, a rich set of values, and a keen sense of storytelling, often infused with humor. He frequently expressed his deep attachment to the Perros-Guirec region and its rugged coastline.
His children’s success was his pride and joy, and he was grateful to them for helping him see the world from new perspectives. His wife was also a great source of happiness, and he often emphasized how she guided him toward a healthier lifestyle. He was glad to have recently reconnected with the values of the land and its bounty, which he had learned in his youth.
Mehdi possessed a vast scientific knowledge extending beyond physics, which he generously shared with colleagues and students alike. He was a committed individual who stood by his convictions and expressed them in passionate discussions. We will deeply miss those moments. Our thoughts are with his family.