Loss induced collective subradiant Dicke behaviour in a multiatom sample

The exact dynamics of N two-level atoms coupled to a common electromagnetic bath and closely located inside a lossy cavity is reported. Stationary radiation trapping effects are found and very transparently interpreted in the context of our approach. We prove that initially injecting one excitation only in the N atoms-cavity system, loss mechanisms asymptotically drive the matter sample toward a long-lived collective subradiant Dicke state. The role played by the closeness of the N atoms with respect to such a cooperative behavior is brought to light and carefully discussed.