Four-channel WDM optical phase conjugator usingfour-wavemixing in a single semiconductor optical amplifier

Abstract
Multichannel optical phase conjugation in a semiconductor optical amplifier (SOA) is reported. A single SOA is used to conjugate four 2.5 Gbit/s WDM channels with 2 nm channel spacings. Our results show that penalties due to crosstalk between channels during conjugation can be acceptably small.