Temporal solitary subpicosecond pulse propagation in a dye-doped polymer slab waveguide with a negative nonlinear refractive index

Subpicosecond (150 fs) temporal solitary pulse propagation is observed in an azo-dye-Disperse Red 1 doped (DR1) polymer waveguide. The negative nonlinear refractive index enables the generation of bright soliton in the medium with positive group velocity dispersion. Moreover, the pulse narrowing up to 97 fs based on the high-order soliton is observed. The magnitude of the nonlinear refractive index of the DR1-doped PMMA (poly[methyl methacrylate] film is estimated by cross-correlation measurement and the assumption-free pulse-form retrieval technique.