With the advancement of nanoscale semiconductor technology,
semiconductor optical amplifiers are used to amplify and process all-optical signals. In
this paper, with the aim of calculating the gain of quantum dot semiconductor optical
amplifier (QD-SOA), two groups of rate equations and the optical signal propagating
equation are used in the active layer of the device. For this purpose, the related
equations are presented coherently. In our model, the rate equations that are ordinary
differential equations (ODE) are solved by the Runge-Kutta method. The rate equations
are based on the occupation probabilities of the energy levels instead of the carrier
densities. On the other hand, the signal propagating equation is a partial differential
equation (PDE) and is solved by using the SLICE technique. Therefore, a suitable
solution for numerical modeling is presented. Based on the presented method, modeling
is implemented in the MATLAB environment. The modeling results show a remarkable
accuracy of the model. Also, the proposed model is simple and the runtime is too short
in comparison with other similar models. Manuscript profile

In this paper, we propose a numerical model for Four-Wave Mixing (FWM)
efficiency in quantum dot semiconductor optical amplifiers (QD-SOAs). Despite the
complexities of the equations governing the QD-SOAs, simple models with short
computational time are essential to analyze and design them. We present equations of
the QD-SOAs coherently and calculate FWM efficiency in the QD-SOA using the
pump/probe technique. In this model, the rate equations take into account the
occupation probabilities of each level instead of the carrier of densities. Moreover, the
transfer matrix based on the pump/probe measurement technique is solved in two
dimensions, space and time, using the Slice technique. The described model is
implemented in the MATLAB environment. The proposed model is simpler than similar
models and has a shorter computational time than them Manuscript profile