Dynamics of a fluid of light

Quentin C. Glorieux, Clara Piekarski, Quentin Schibler +2 more

Eiichi Hanamura, Yutaka Kawabe, Akio Yamanaka

Heitor Victor Santos da SILVA

The propagation of light in nonlinear media is well described by a 2D nonlinear Schrödinger equation (NLSE) within the paraxial approximation, which is equivalent to the GrossPitaevskii equation (GPE), the mean-field description for the dynamics of Bose-Einstein condensates (BECs). As a product of this similarity, we can establish the figure of a quantum fluid of light. Quantum fluids of light have been used for theoretical and experimental investigations of phenomena already studied and realised in BECs. In this thesis, we describe the mechanisms that make the conception of a quantum fluid of light possible for different experimental platforms. Furthermore, we present a study on the formation of self-bound droplets of light in hot atomic vapours, our chosen nonlinear medium, in an attempt to obtain a mapping between experimental parameters typically used in BEC experiments and those needed to observe the analogous phenomenon in atomic vapours. We investigate the static properties of the system, providing a phase diagram for the different and possible solutions for the optical regimes of interest. Finally, we systematically study droplet dynamics, focusing on the behaviour of the collective monopole excitation and the dynamic formation of these objects under realistic experimental conditions.

Claire Michel, Matthieu Bellec

Experiments probing quasiparticles in semiconductor microcavities offer unprecedented insights into the dynamics of quantum fluids of light.

C. di Lauro

Amit Vashisht, Maxime Richard, Anna Minguzzi

We study the Bose polaron problem in a nonequilibrium setting, by considering an impurity embedded in a quantum fluid of light realized by exciton-polaritons in a microcavity, subject to a coherent drive and dissipation on account of pump and cavity losses. We obtain the polaron effective mass, the drag force acting on the impurity, and determine polaron trajectories at a semiclassical level. We find different dynamical regimes, originating from the unique features of the excitation spectrum of driven-dissipative polariton fluids, in particular a non-trivial regime of acceleration against the flow. Our work promotes the study of impurity dynamics as an alternative testbed for probing superfluidity in quantum fluids of light.