Reflective semiconductor optical amplifier with segmented electrodes for high-speed self-seeded colorless transmitter

A self-seeded reflective semiconductor optical amplifier (RSOA) has been viewed as an attractive candidate for the low-cost colorless transmitter in wavelength-division-multiplexed passive-optical networks (WDM-PON). In this paper, we propose and demonstrate the use of two-section RSOA with segmented electrodes to simultaneously improve the modulation bandwidth and extinction ratio in a self-seeded operation. We first find the optimal driving condition to induce strong modulation cancellation by analyzing the gain dynamics inside the RSOA. In addition, we experimentally confirm the improvement in direct modulation bandwidth by segmenting the electrodes. Finally, we employ the two-section RSOA in a self-seeded system and successfully demonstrate transmission over a 25-km standard single-mode fiber at 5 Gb/s as well as improved back-to-back modulation at 10-Gb/s in C-band by using the optimal driving condition.