Signatures of the Anderson localization excited by an optical frequency comb

We investigate Anderson localization of light as occurring in ultra-short excitations. A theory based on time dependent coupled-mode equations predicts universal features in the spectrum of the transmitted pulse. In particular, the process of strong localization of light is shown to correspond to the formation of peaks in both the amplitude and in the group delay of the transmitted pulse. Parallel ab-initio simulations made with Finite-Difference Time Domain codes and molecular dynamics confirm theoretical predictions, while showing that there exist an optimal degree of disorder for the strong localization.