Modified split-step fourier method for the numerical simulation of solitonamplification in erbium-doped fibers with forward-propagating noise

Using a modified version of the split-step Fourier method, we analyze the e ffect of noise on soliton propagation inside erbium-doped fiber amplifiers. In fact, noise from forward-propagating amplified spontaneous emission, as sociated with a Markov immigration process, is included in the analysis of soliton amplification. Moreover, this algorithm accounts for the real spect ral gain profile of the fiber amplifier. The frequency jitter, induced duri ng soliton amplification, is compared with the Gordon-Haus effect where opt ical amplifiers are considered as noisy point-like devices.