Observation of a super-radiant phase transition using a cloud of laser cooled atoms in free space

SPICE Workshop on Quantum Spinoptics, June 13th - 15th 2023

Antoine Browaeys

This talk will present our recent work on the realization of the Driven Dicke model using an elongated cloud of cold atoms in free space (arXiv:2207.10361). This model considers the collective spin of an ensemble of 2 level-atoms coupled to a single mode of the electromagnetic field and driven by a classical light. We observe experimentally the non-equilibrium phase transition predicted by the model, featuring a super-radiant phase at strong intensity of the driving laser and a phase characterized by a collective dipole at weak driving. We also measure the statistics of the emitted light and find that it has the properties predicted for a super-radiant laser.