Expérimental
Merging nonlinear optics and quantum hydrodynamics, quantum fluids of light have gained great interest in the past few years. Indeed, in properly engineered experimental optical devices, photons can acquire an effective mass and be in a fully controlled effective interaction. They behave collectively as a quantum fluid, and share remarkable common features with other systems such as superfluidity and quantum turbulence. Quantum fluids of light have been investigated mainly in one and two dimensions in various photonic platforms. At INPHYNI, in the Waves in Complex Systems group, we have implemented an experimental platform which basically consists in propagating a continuous laser beam in a nonlinear biased photorefractive crystal (Strontium Barium Niobate, SBN). In such a configuration, the evolution of the transverse optical field along the propagation axis is analogous to a 2D quantum fluid evolving in time. A major challenge in the field of quantum fluids of light is to increase its dimensions. An interesting strategy is to consider ultrashort pulses rather than continuous propagation and combine both the instantaneous electronic Kerr effect with the slow photorefractive nonlinear effect. In this context, the goal of this internship is two-fold. The first part will be to characterize the slow photorefractive response of the biased SBN crystal, the second part will be to accurately measure its instantaneous nonlinear optical response.