Recovery dynamics of cross-modulated beam phase in semiconductor amplifiers and applications to all-optical signal processing

An analysis of the cross-phase modulation of a lightwave beam using a short optical pulse excitation is presented as a function of the saturation leve l of a semiconductor optical amplifier. The optical phase response is chara cterised by introducing a new recovery time parameter useful for the analys is of phase modulation-based applications. It is shown that, unlike the 10- 90% recovery time, the parameter increases with amplifier saturation. A com parison through computer simulations between the operation characteristics of a wavelength converter and a time-division demultiplexer is carried out in the light of this parameter, which it is shown to be the limiting factor for fast operation of the latter device. (C) 2001 Elsevier Science B.V. Al l rights reserved.