Generating long-lived entangled states with free-space collective spontaneous emission

Considering the paradigmatic case of a cloud of two-level atoms interacting through common vacuum modes, we show how cooperative spontaneous emission, which is at the origin of superradiance, leads the system to long-lived entangled states at late times. These subradiant modes are characterized by an entanglement between all particles, independently of their geometrical configuration. While there is no threshold on the interaction strength necessary to entangle all particles, stronger interactions lead to longer-lived entanglement.

Automated summary

By studying the interaction between two-level atoms through shared vacuum modes, we found that cooperative spontaneous emission leads to the formation of long-lived entangled states at later stages, which are independent of the geometric configuration.