Interactive model of Purcell-Dicke enhancement

We compute the design parameters that maximize the cooperative decay rate (CDR) from a nanosphere of identical two-level atoms phased to radiate coherently (Dicke enhancement), encased in a shell of a noble metal (Purcell effect), the whole suspended for mechanical support in a dielectric medium extending to infinity. Both the radiating core and the metallic shell are described internally by their respective frequency-dependent dielectric functions. (In previous papers one or the other medium was given a fixed dielectric constant.) The solution is noticeably altered, and the enhancement increased, when both media respond interactively to one another.