Saturation induced by picosecond pulses in semiconductor optical amplifiers

Abstract
We study the amplification of picosecond pulses in a semiconductor optical amplifier, including the effect of carrier heating and spectral-hole burning. Under simplifying approximations we obtain an analytical expression for the amplifier output to a given picosecond pulse input. The effect of the intraband dynamics becomes important for pulses below a critical pulse width that is related to the K factor that characterizes the modulation properties of semiconductor lasers. The critical pulse width ranges from a few picoseconds to 20 ps in most cases.