Two-Level Laser-like Emission by the Interaction of Self-Induced   Transparency Solitons and Surface Anderson Localizations of Light
  Self-induced transparency pulses propagating in a random medium embedded in a two-level system can transfer energy to localized Anderson states. This allows the onset of two-level laser-like action. 
Viola Folli and Claudio Conti
physics.optics cond-mat.dis-nn cond-mat.stat-mech