Quantum-Dot Semiconductor Optical Amplifiers: State Space Model versus Rate Equation Model

Figure 1

Schematic representation of QD-SOA with dots-in-a-well (DWELL) structure, where a sevenfold-stacked self-assembled InAs QD active region is sandwiched between two AlGaAs cladding layers. InAs QDs are covered with a 5 nm thick InGaAs capping layer. The QD layers are separated by 33 nm thick GaAs spacer layers which are considered for strain relaxation.