A novel transmission line model for quantum well semiconductor optical amplifiers

This paper presents a new wideband model for quantum well semiconductor optical amplifiers (QW-SOAs) based on quantum well transmission line modelling (QW-TLM) method to facilitate the performance analysis of QW-SOAs. The dynamic process of electron-photon interactions during the photon propagation has been considered in this model. The gain and spontaneous emission spectra obtained by this model are in very agreement with those obtained by the analytical expression within a wide spectra band ranging from 1300nm to1700nm. The temporal and spectral output waveforms of the pulse input signal having the peak power values of 0.1mw and 1mw are studied and it was found that the new model can accurately predict the temporal and spectral behaviours of the amplified output signal, spectral broadening, red shift and temporal distortion induced by the gain saturation.