Triangular pulses in normally dispersive optical fibers

Nonlinear reshaping of ultrashort optical pulses in normally dispersive single-mode optical fibers is analyzed numerically applying extended nonlinear Schrödinger equation. Formation of triangular pulses depending on initial pulse waveform (Gaussian, secant and super-Gaussian) is analyzed. It is found that fully triangular pulses as transient state can be formed from initial Gaussian waveforms at the particular propagation distance.