Loadable and erasable optical buffer based on a semiconductor optical amplifier with background noise suppression

A loadable and erasable fiber loop optical buffer based on a semiconductor optical amplifier (SOA) is presented. Two SOAs in our configuration not only provide nonlinear phase shift to implement buffer function, but also compensate for the propagation attenuation during long time storage. In particular, we present a simplified model to investigate the influence of background noise to the optical buffer performance. Both theoretical and experimental results reveal that the background noise can be suppressed by intentionally increasing the fiber loop loss. We also demonstrate that the packet pattern is well maintained after a storage time of 145 μs without self-oscillation.