Lattice hyper-solitons in photorrefractive materials
  We show a novel kind of nonlinear waves in two-dimensional photonic lattices. This waves take the form of light clusters that may fill an arbitrary number of lattice sites. We have demonstrated by numerical simulations that stable propagation can be achieved under adequate conditions and we have described the unstable patterns developed otherwise. Our results show that these new kind of nonlinear waves can be easily found in current experiments. 
Jose Ramon Salgueiro, Humberto Michinel and Maria I. Rodas-Verde