Pulse train generation by soliton fission in highly nonlinear chalcogenide (As2S3) waveguide Bragg grating

The conversion of a 3.9 ps optical pulse into a train of six 450 fs pulses within a 37 mm length of a highly nonlinear chalcogenide (As₂S₃) waveguide Bragg grating is reported. Here, the initial pulse develops into a sixth-order soliton and is split into its six fundamental solitons through soliton fission. The very large optical nonlinearity and strong photosensitivity of As₂S₃ enables the use of pulses that are 25 ?? shorter than in previous experiments, and have 500??less energy. The results are compared to numerical modelling using the nonlinear coupled mode equations and find satisfactory agreement between experiment and theory after accounting for imperfections observed in the grating.