SOA-NOLM Based Device for Increasing the Extinction Ratio and Attenuation of Unmodulated Content of an Optical Carrier

This paper describes the experimental demonstration of a fibre-optic device able to attenuate the unmodulated content and simultaneously enhances the extinction ratio (ER) of an optical carrier. The main aim is to show the proof-of-concept. The active device configuration is based on a Nonlinear Optical Loop Mirror (NOLM) incorporating a Semiconductor Optical Amplifier (SOA) as a compact non-linear element. Results show a 14.6 dB increase of extinction ratio (ER). The unmodulated optical offset could be reduced by 11.2 dB.