Nonequilibrium states of a plasmonic Dicke model with coherent and dissipative surface-plasmon-quantum-emitter interactions

Hybrid photonic-plasmonic nanostructures allow one to engineer coupling of quantum emitters and cavity modes accounting for the direct coherent and environment-mediated dissipative pathways. Using the generalized plasmonic Dicke model, we explore the nonequilibrium phase diagram with respect to these interactions. The analysis shows that their interplay results in the extension of the superradiant and regular lasing states to the dissipative coupling regime and an emergent lasing phase without population inversion having a boundary with the superradiant and normal states. Calculated photon emission spectra are demonstrated to carry distinct signatures of these phases.