This work is published on 21 October 2019 in the journal PNAS.
For more information, see the fullPress release of Claude Bernard Lyon 1 University and the CNRS (in French).
*Research structures involved: Institut de physique des 2 infinis de Lyon (IP2I ‒ Université Lyon 1 / CNRS), Laboratoire interdisciplinaire de physique (LIPhy ‒ Université Grenoble Alpes / CNRS), Institut für Lonenphysik und Angewandte Physik (Université d’Innsbruck, Autriche), Atomic, Molecular & Optics Physics Laboratory (RIKEN, Japon), l’International research laboratory FJPPL-TYL (CNRS/CEA/KEK)