Mutual Seeding of Directly Modulated R-SOAs for Full-Duplex and Single-Wavelength Short Reaches

We demonstrate experimentally a novel mutual-seeding configuration for reflective semiconductor optical amplifier that allows for seamless bidirectional transmission on the same wavelength. This configuration extends the well-known self-seeding features, i.e., automatic tuning and direct modulation, while it removes the need for the Faraday mirror. For the first time, a mutual-seeding cavity is realized by the whole optical link: two R-SOAs (one at each link end) simultaneously act as direct modulators and seed each other. The key to achieve this relevant system simplification is a simple cancellation algorithm.