A new setup for studying many-body physics with Rydberg superatoms strongly coupled to an optical cavity

In cavity quantum electrodynamics (cQED) systems, the realization of strong coupling between light and two-level systems plays a critical role in the study of quantum optics and many body physics. In the optical domain, strong coupling between light and a single atom has led to the generation of photonic quantum gates. The nonlinear interaction in an optical cavity also enables the study of spin squeezing. However, the generation of strong coupling between optical photons and many two-level systems remains a challenge. Here, we introduce a new optical cQED setup which can increase light-atom interactions by coupling Rydberg superatoms to a high-finesse optical cavity. The collective excitation in a Rydberg superatom creates an effective two-level system with the coupling strength enhanced by the atom number in the ensemble. Combining the superatoms with the high-finesse cavity, we expect to observe an effective single-atom cooperativity more than 1000. I will present the progress toward realizing strong coupling in this setup. I will also discuss the potential of studying interactions between two superatoms and long-range spin Hamiltonians.