Quantum-dot semiconductor optical amplifiers for high bit-rate signal processing over 40 Gbit/s

This paper provides a theory and simulation of traveling-type semiconductor optical amplifiers (SOAs) with self-assembled quantum dots in their active region. We calculated their continuous-wave and 40-Gbit/s dynamic performance, and compared them with 1.55-mum SOAs with bulk InGaAsP active layers. The results demonstrate that quantum-dot SOAs can process multiple-wavelength high bit-rate optical pulse trains over 40 Gbit/s under gain saturation. This promises diverse functions like regeneration, reshaping, multiple-wavelength processing, wavelength conversion, and demultiplexing of high-bit-rate patterned optical signals, which meet with the demand of next-generation broadband all-optical photonic networks.