  Photon correlations and cross-correlations of light scattered by a regular
structure of strongly driven atoms are investigated. At strong driving, the
scattered light separates into distinct spectral bands, such that each band can
be treated as independent, thus extending the set of observables. We focus on
second-order intensity-intensity correlation functions in two- and multi-atom
systems. We demonstrate that for a single two-photon detector as, e.g., in
lithography, increasing the driving field intensity leads to an increased
spatial resolution of the second-order two-atom interference pattern. We show
that the cross-correlations between photons emitted in the spectral sidebands
violate Cauchy-Schwartz inequalities, and that their emission ordering cannot
be predicted. Finally, the results are generalized for multi-particle
structures, where we find results different from those in a Dicke-type sample.
