Polarization-sensitive performance of strained-quantum-well semiconductor optical amplifiers

Comparing with EDFA, one prominent disadvantage of semiconductor optical amplifier (SOA) is that its gain is sensitive to the state of polarization of incident light. Reducing the polarization sensitivity of SOA is one of the important aims that man goes in for in the research of SOA. In this paper, we analyze the polarization performance of SOA, and also successfully develop a mixed-strain quantum well, polarization insensitive SOA. Ultra low residual reflectivity film is coated on the cleaved ends of active- layer to eliminate the resonant effect of the cavity and suppress self-simulated emission, thus the incident optical signals could obtain single path gain while traveling through the active-layer, which forms the traveling-wave amplification.