Detailed Dynamic Model for Semiconductor Optical Amplifiers and Their Crosstalk and Intermodulation Distortion

An advanced dynamic model for multisection semiconductor optical amplifiers is Presented. It accounts for the carrier and field distributions in the longitudinal direction as well as for the facet reflectivities. The model can handle arbitrary time-varying input signals and current modulations. Here the model is used to assess intermodulation distortion and crosstalk. First, cascaded amplifiers are considered, and the crosstalk and intermodulation distortion due to cascaded amplifiers are found number of cascaded amplifiers in multichannel systems. Carrierfor 25 dB of single-pass gain, a reflectivity of 5 x 10-4 will the numerical and experimental results for crosstalk and inresult in 3-dB excess distortion. Reduction of intermodulation termodulation distortion in a two-channel svstem with two modulation due to current modulation. Experimental measurements of intermodulation distortion and crosstalk, where nearly traveling-wave amplifiers are used, verify the validity of the Section 11 describes a numerical model that can handle carrier-density-induced nonlinearities due to multichannel amplification. Section 111 presents a two-channel experimental to accumulate by adding together in amplitude; this may limit the induced nonlinearities depend strongly on facet reflectivities; setup with a self-heterodyne detection technique, which proa large dynamic measurement range. Section IV gives distortion by use of multisection amplifiers is found to be possible only for small channel separations (< 300 MHz). Simulations of 11-channel amplification showed a reduction of 13 dB in intermodulation distortion when random-phase optical carriers are applied.