Ultra-wide, 75 nm 3 dB gain-band optical amplifierutilising gain-flattenederbium-doped fluoride fibre amplifier and discrete Raman amplification

Abstract
A 3 dB gain bandwidth of 75 nm (1531–1606 nm) is realised in a novel configuration of a two-stage erbium-doped fluoride fibre amplifier with a discrete fibre Raman amplifier. Error-free operation in an in-line amplifier configuration is also confirmed through a WDM (2.5 Gbit/s × 9 channel) transmission experiment.