Many-Body Radiative Decay in Strongly Interacting Rydberg Ensembles br

When atoms are excited to high-lying Rydberg states they interact strongly with dipolar forces. Theresulting state-dependent level shifts allow us to study many-body systems displaying intriguingnonequilibrium phenomena, such as constrained spin systems, and are at the heart of numeroustechnological applications, e.g., in quantum simulation and computation platforms. Here, we show thatthese interactions also have a significant impact on dissipative effects caused by the inevitable coupling ofRydberg atoms to the surrounding electromagnetic field. We demonstrate that their presence modifies thefrequency of the photons emitted from the Rydberg atoms, making it dependent on the local neighborhoodof the emitting atom. Interactions among Rydberg atoms thus turn spontaneous emission into a many-bodyprocess which manifests, in a thermodynamically consistent Markovian setting, in the emergence ofcollective jump operators in the quantum master equation governing the dynamics. We discuss how thiscollective dissipation-stemming from a mechanism different from the much studied superradiance andsubradiance-accelerates decoherence and affects dissipative phase transitions in Rydberg ensembles