PhD defense — Myrann Baker-Rasooli

Myrann is now doctor! After a few years of hard work, he defended his PhD thesis entitled “Vortex and solitons dynamics in quantum fluids of light”.

Amazing work, congrats Myrann!

Thesis summary

In this work, we use quantum fluids of light as a versatile platform to explore superfluid hydrodynamics and out-of-equilibrium phenomena. By propagating a near-resonant laser beam through a hot atomic vapor, we create a two-dimensional photon fluid whose dynamics obey the same equations as those governing quantum gases with repulsive interactions. This optical system offers full access to both density and phase, enabling the direct observation of complex flow patterns and vortex dynamics. We first establish the fundamental properties of this platform and its experimental realization. We then investigate various hydrodynamic regimes, from turbulent vortex ensembles exhibiting energy cascades to the controlled interaction of a few quantized vortices. These studies reveal phenomena such as the formation of dark solitons from vortex dipoles, the collapse of vortex leapfrogging into dispersive shock waves, and the self-propulsion of optical defects through vortex emission. Altogether, this thesis demonstrates the unique ability of quantum fluids of light to emulate quantum hydrodynamics and provides new insights into the microscopic mechanisms driving superfluid turbulence.