Spatial storage of discrete dark solitons

The interaction between a mobile discrete dark soliton (DDS) and impurities in one-dimensional nonlinear (Kerr) photonic lattices is studied. We found that the scattering is an inelastic process where the DDS can be reflected or transmitted depending on its transversal speed and the strength of the impurities. In particular, in the reflection regime, the DDS increases its transversal speed after each scattering. A method for spatial storage of DDS solutions using two impurities is discussed, where the soliton can be trapped within a storage region until it reaches the critical speed needed to be transmitted. We show, numerically, that this method allows the storage of multiple DDS simultaneously.