Kick-off of ANR "CRITICLAS" (PI R. Bertoni, IPR)

Understanding fundamental interactions within the system (electron-electron and electron-phonon) to control emerging cooperative effects

Recently, materials science has moved from phenomenological observation of emerging electronic or structural orders to the control and harvest of the peculiar properties offered by those very materials. From that perspective, a key scientific goal is to understand fundamental interactions (electron-electron and electron-phonon) for controlling cooperative phenomena in material. In addition to thermal equilibrium control of physical properties, photo-induced phenomena represent a fascinating route for ultrafast and out-of-equilibrium photo-control of materials. This emerging technique consists in perturbing the system with an ultrashort and intense light pulse tune to specific electronic resonances. The goal of this project is to study giant and ultrafast photo-response of correlated molecular materials around critical points of their phase diagram. The main idea is to couple a cryogenic He gas-based pressure-temperature cell with the existing femtosecond spectroscopy platform, for combining both optical and physical controls and monitoring the hopefully large photo-response of MOCs. We hope to go beyond the conventional linear response on light excitation to observe non-conventional and “non-statistical” states in correlated materials, possibly hidden at thermal equilibrium.