Influence of gain coefficient on the self-similar pulses propagation in a dispersion-decreasing fiber

This paper first investigates the influence of the dispersion-decreasing optical fiber structure on the self-similar pulses interaction and compression. The dynamic of the evolution of a pair of self-similar pulses in a dispersion-decreasing optical fiber with normal group-velocity dispersion (ND-DDF) under different gain coefficient g0 of DDF is analyzed, and the chirp evolution is also studied to analyze the propagation characteristic of self-similar pulses. The numerical simulations show that the change of gain coefficient g0 of DDF can impact directly on the linear chirp of the self-similar pulses. We find out that the smaller g0 can generate better high-quality femto-second pulses than the higher g0 after pulses compression. Finally, we got a pair of ultra-short pulses with a FWHM of 124 fs at g0 = 0.015 m−1, indicating efficient and high-quality pulse compression.