Structure analysis of two-dimensional nonlinear self-trapped photonic   lattices in anisotropic photorefractive media
  We generate experimentally different types of two-dimensional self-trapped photonic lattices in a photorefractive medium and analyze the induced refractive index change using two different methods. One method gives the first experimental Fourier space analysis of both linear and nonlinear self-trapped photonic lattices with periodic phase modulation using partially spatially incoherent multi-band excitation of the lattice modes. The other method utilizes the waveguiding properties of the lattice to achieve a real space analysis of the induced refractive index change. The results of both methods are compared. 
Bernd Terhalle, Denis Traeger, Liqin Tang, Joerg Imbrock, and Cornelia   Denz