  We describe the possibility of drastically boosting the spontaneous emission
of a collection of two-level quantum emitters by embedding them in an
epsilon-near-zero (ENZ) environment, consisting of a plasmonic waveguide
operated at cut-off. This phenomenon relies on the combination of Purcell
enhancement and Dicke superradiance effects, exploiting the large and uniform
local density of states in ENZ channels, which is shown to significantly extend
the spatial extent of these quantum effects. We envision exciting applications
in optical sensing, molecular detection and low-threshold lasing.
