75-nm 3-dB gain-band optical amplification with erbium-doped fluoride fibre amplifiers and distributed Raman amplifiers in 9/spl times/2.5-Gb/s WDM transmission experiment

An extremely large 3-dB gain-bandwidth of 75 nm (1531-1606 nm) is achieved employing partially gain-flattened erbium-doped fluoride fiber amplifiers and Raman amplification in the transmission fibres. 9/spl times/2.5 Gb/s WDM transmission is successfully demonstrated using our amplifiers as an in-line- and pre-amplifiers.