Crossover from self-defocusing to discrete trapping in nonlinear waveguide arrays

Matuszewski, Michal; Rosberg, Christian R.; Neshev, Dragomir N.; Sukhorukov, Andrey A.; Mitchell, Arnan; Trippenbach, Marek; Austin, Michael W.; Krolikowski, Wieslaw; Kivshar, Yuri S.

Crossover from self-defocusing to discrete trapping in nonlinear waveguide arrays

Authors

Matuszewski, Michal

Rosberg, Christian R.

Neshev, Dragomir N.

Sukhorukov, Andrey A.

Description

We predict a sharp crossover from nonlinear self-defocusing to discrete self-trapping of a narrow Gaussian beam with the increase of the refractive index contrast in a periodic photonic lattice. We demonstrate experimentally nonlinear discrete localization of light with defocusing nonlinearity by single site excitation in LiNbO$_3$ waveguide arrays.
6 pages, 4 figures