Localized modes in mini-gaps opened by periodically modulated intersite   coupling in two-dimensional nonlinear lattices
  Spatially periodic modulation of the intersite coupling in two-dimensional (2D) nonlinear lattices modifies the eigenvalue spectrum by opening mini-gaps in it. This work aims to build stable localized modes in the new bandgaps. Numerical analysis shows that single-peak and composite two- and four-peak discrete static solitons and breathers emerge as such modes in certain parameter areas inside the mini-gaps of the 2D superlattice induced by the periodic modulation of the intersite coupling along both directions.The single-peak solitons and four-peak discrete solitons are stable in a part of their existence domain, while unstable stationary states (in particular, two-soliton complexes) may readily transform into robust localized breathers. 
Goran Gligori\'c, Aleksandra Maluckov, Ljup\v{c}o Had\v{z}ievski,   Boris A. Malomed
nlin.PS