Cascadability improvement of semiconductor optical amplifier based gates using polarization multiplexing technique

Cascaded semiconductor optical amplifier (SOA) gates using polarization mul tiplexing technique (PMT) are experimentally demonstrated for the first tim e. The penalty is smaller than 1 dB after three SOA gates. Numerical simula tion shows that cascaded SOA gates operated at single-channel can endure so me gain polarization sensitivity (GPS) of the SOA, but, even a small GPS wi ll rapidly reduce the number of cascaded SOA gates operated at multi-channe ls. Experiment shows that in addition to GPS, four-wave mixing (FWM) will a lso affect the performance of SOA gates when operated in a multi-channel sy stem. (C) 2000 Elsevier Science B.V. All rights reserved.