We observe experimentally higher-order solitons in waveguide arrays with defocusing saturable nonlinearity. Such solitons can comprise several in-phase bright spots and are stable above a critical power threshold. We elucidate the impact of the nonlinearity saturation on the domains of existence and stability of the observed complex soliton states.
Smirnov, E., Rüter, C., Kip, D., Kartashov, Y.V., Torner, L. Observation of higher-order solitons in defocusing waveguide arrays. "Optics letters", Juliol 2007, vol. 32, núm. 13, p. 1950-1952.