Pattern effect mitigation in high-speed all-optical switch based on cross-gain modulation in two SOAs with different bandgaps

摘要

Two cascaded semiconductor optical amplifiers (SOAs) with different bandgaps are proposed as an all-optical switch based on cross-gain modulation (XGM) to reduce the pattern effect inflicted by a carrier-lifetime-related long-lived gain recovery tail. We numerically investigate the device gain recovery dynamics in such setup excited by 100 Gbit/s pseudorandom return-to-zero control signal at 1520 nm for different probe wavelengths. The preliminary simulation results indicate that the pattern effect in a SOA in which control pulses are localized in gain region can be reduced by a concatenated SOA in which control pulses are situated in the absorption region. This compensation principle is always valid when the bit rate is beyond 100 Gbit/s.