Nonlinear distortion generated by semiconductor optical amplifier boosters in analog optical systems

Closed-form theoretical expressions for the second- and third-order harmonic distortions generated by a semi-conductor optical amplifier (SOA) operating under slight saturation conditions are derived for what is believed to be the first time. The distortion results provided by these expressions agree very well with those obtained by means of simulation and experiments, showing that one should carefully adjust the optical power launched into the SOA to obtain both the good linearity and high dynamic range required by analog optical systems.