Slow-Light Spatial Solitons

Slow light has attracted a great deal of attention recently because of many motivations, ranging from fundamental interests to applications in quantum information such as quantum memories, or to optical information management by a controllable time delay between data packets (network buffering, data synchronization) [1]. The main physical origin that leads to the slow or fast light relies on the control of the group velocity of a signal by inducing a strong material dispersion in the medium in the vicinity of the frequency of the signal. This control can be achieved by different means and in different materials. In a resonant optical material, the change of the group index near a resonance leads to the strong decrease of the group velocity which is intimately linked to a strong absorption. To remove this detrimental absorption, efficient methods for generating a very narrow hole in the absorption line have been performed by using quantum coherence properties of atomic media, such as electromagnetically induced transparency (EIT) in ultracold atomic gases [2],