We report what we believe is the first observation of modulation instability in the anomalous-diffraction regions of a photonic lattice. The experiments were carried out in a 1D waveguide array fabricated in a lithium niobate crystal displaying the photovoltaic self-defocusing nonlinearity, and our results are confirmed numerically by simulating the nonlinear beam propagation.
© 2006 Optical Society of America
Milutin Stepic, Christian Wirth, Christian E. Rüter, and Detlef Kip, "Observation of modulational instability in discrete media with self-defocusing nonlinearity," Opt. Lett. 31, 247-249 (2006)