Dynamic gain equalization of erbium-doped fiber amplifier with all-fiber acousto-optic tunable filters

Summary form only given. In this work, we demonstrate a dynamic gain equalization of an EDFA by employing an all-fiber active filter with low loss and low polarization dependence as a mid-stage gain-flattening element. In contrast to other active gain clamping schemes, such as pump-power adjustment or all-optical feedback loop, that ensure gain flatness only at a particular gain level, our dynamic approach enables us to achieve a good gain flatness (<0.7 dB) over a broad wavelength span (>35 nm) at a wide range of operational gain levels as well as input signal and pump powers. Our gain-flattening filter consists of two all-fiber acousto-optic tunable filters (AOTFs) in series.