Amplification and Generation of Frequency-Modulated Soliton Pulses in Nonuniform Active Fiber Configurations

We report on the theoretical and numerical analysis of nonlinear Schrödinger equation describing dynamical evolution frequency-modulated (FM) optical signals propagating through fiber configuration comprising active fibers with anomalous dispersion nonuniformly distributed over length. In our consideration, a single section including segments initially increasing then decreasing is used for amplification compression an external FM pulse resulting in increase ~6 orders magnitude peak power 100-fold narrowing duration down to few picoseconds. Moreover, we demonstrate that, ~1 mW weakly modulated continuous wave input signal, two sections different profiles able generate strongly periodic train, repetition rate >100 GHz, ~0.5 ps, up kW. An governed by modulation instability both configurations explored.