The collective interaction of a multiparticle three-level near-equispaced ladder system with an external applied coherent field, damped via the surrounding electromagnetic field modes, is investigated. The absorption-emission properties of such a medium are shown to be adjustable via external parameters. It is demonstrated that under special conditions the collective resonance fluorescence spectral lines are narrower than the natural bandwidths. Ultranarrow spectral lines are obtained if the laser-atom interaction is mediated by an electromagnetic bath that possesses nonclassical features. Moreover, in these processes an intense flux (intensity proportional to N2) of superbunched photons with subnatural spectral widths can be generated. Artificial atoms (i.e., quantum wells or quantum dots) are suggested as an appropriate system.