Three directions in the physics of driven quantum fluids

In driven-dissipative polariton fluids, condensation, superfluidity and collective excitations acquire behaviours that have no equilibrium analogue. We study the phase transitions of these systems (Goldstone and Higgs modes, critical behaviour, universality classes) and how the drive itself can trigger, control and reshape them: opening real and imaginary gaps, engineering Thouless-pump-like dynamics, and steering transitions with an external laser.

Polariton fluids are simulators of quantum field theory in curved spacetimes. By sculpting the flow we build acoustic horizons and ergoregions, and look for their signatures: Hawking radiation, superradiance à la Zeldovich-Penrose, and the entanglement generated when a massless field scatters at the horizon. This is the heart of the ANR Hawk project.

We are developing polariton networks as quantum reservoirs for the generation and sensing of arbitrary quantum states of light, a route to quantum-enhanced computation and metrology on a photonic platform. The work is carried out within the European QONE Pathfinder project, in collaboration with the group of T. C. H. Liew.