Ultrafast and giant photo-response of molecular conductors near critical points – CRITICLAS

Materials science has moved from the observation to the control of the properties offered by complex systems. Along this line, mastering electronic correlations remains one of the great challenge in solid-state physics. A robust testbed for studying such phenomena are the molecular correlated materials that display competing orders and phase transitions, such as metal to insulator. CRITICLAS proposes to investigate the response of molecular conductors to ultrafast photo-excitations near critical points of the phase diagram, that is where the susceptibilities of materials diverge. It will rely on a challenging combination of accurate control of thermodynamical parameters (pressure, temperature) with ultrafast pump-probe optical spectroscopy. In this way, we aim to build a unique setup that will combine a cryogenic high pressure gas cell to a femtosecond laser platform. The objective is to see beyond the limits of a linear response and observe non-statistical hidden states in correlated materials. It may drive spectacular effects triggered by collective, coherent and gigantic photo-response.