Benoît Deveaud, 67, is a specialist in optical spectroscopy of semiconductors, with a particular dedication to the ultrafast and quantum optical properties of semiconductor nanostructures.
His PhD thesis has cast a profound understanding of the properties of chromium, as a deep impurity center, in Gallium Arsenide (GaAs). During his post-doctorate at Bell Labs (1986-1987), and the years following at CNET (1987-1993), he has implemented the first sub-picosecond luminescence set-up, with 300 femtosecond resolution, and studied phenomena of major interest in micro and nanostructures, such as the capture of electrons and holes in quantum wells, their intersubband scattering dynamics, the vertical transport of electrons in superlattices, the radiative behavior of excitons or plasmas in quantum wells and quantum wires.
Over the 25 years spent at EPFL in Lausanne, where he has been the director of the Institute of Quantum Electronics and Photonics for more than 10 years, he has expanded the knowledge of his team towards coherent optical spectroscopy by developing a whole ensemble of actively stabilized interferometers. The realization of coherent control experiments on polaritons in a configuration of parametric amplification, the demonstration of the coherent nature of Rayleigh scattering with respect to the phase of the exciting laser were the first steps of the route which leads to a profound understanding of the physics of semiconductor microcavities, in particular of their dynamics in the non-linear regime.
Such an extensive expertise has been essential to his team, within an international collaboration, to probe and assess, for the first time, the Bose Einstein condensation of polaritons in solid-state physics. Benoît Deveaud’s team has further reported observations of polariton fluids including full and half vortices in condensates, Josephson oscillations, dark solitons with break-up of a polariton superfluid into pairs of vortices and finally the observation of the Feshbach resonance for polaritons.
Since April 2017, Benoît Deveaud is the Vice Provost for Research at École Polytechnique (France), in charge of the entire École Polytechnique Research Center, in coordination with its different partners. He is also heading the science advisory committee of the Institut Polytechnique de Paris, grouping together École Polytechnique, ENSAE, ENSTA, Télécom ParisTech and Télécom Sud-Paris.
Article posté le 06/06/2019