Cooperative effects in thin dielectric layers: Long-range Dicke superradiance

We present a theoretical study of cooperative light–matter interactions in quantum emitters embedded within thin dielectric layers. Using a Green's function master-equation approach, we show that the slab geometry fundamentally alters photon-mediated dipole–dipole coupling, extending its range and enabling Dicke-type superradiance even for emitters separated by many wavelengths. Guided slab modes slow the decay of emitter coupling, allowing total and directional superradiance in both linear and planar arrays. Unlike in homogeneous media, collective decay rates scale superradiantly over extended distances and exhibit strong emission anisotropy governed by slab thickness and refractive index. These findings reveal a new regime of long-range cooperative emission, bridging many-body quantum optics and photonic engineering, and suggest scalable pathways toward directional quantum light sources and coherent solid-state emitter arrays.