Intensity effects of light coupling to one- or two-atom arrays of infinite extent

We theoretically and computationally investigate the behavior of infinite atom arrays when illuminated by nearly resonant light. We use higher-order mean-field equations to investigate the coherent reflection and transmission and incoherent scattering of photons from a single array and from a pair of arrays as a function of detuning for different values of the Rabi frequency. For the single array case, we show how increasing the light intensity changes the probabilities for these different processes. For example, the incoherent scattering probability initially increases with light intensity before decreasing at higher values. For a pair of parallel arrays at near resonant separation, the effects from increasing light intensity can become apparent with incredibly low-intensity light. In addition, we derive the higher-order mean-field equations for these infinite arrays, giving a representation that can be evaluated with a finite number of equations.