10 and 80 GHz soliton transmission over 60 km distributed erbium-doped fibre

Soliton communications technology has become a promising candidate for the next generation of high speed long-haul optical transmission systems, mainly due to the rapid development of discrete erbium-doped fibre amplifiers (EDFA). However, the requirement that the amplifier spacing must be much smaller than the soliton period may make the amplifier spacing impratically small for line rates above 50 Gbit/s. It is still difficult to control the fibre dispersion zero to within a fraction of a nanometre during fabrication, and thus the yield of useful fibre will be low. One solution to this problem is to use distributed erbium-doped fibre (DEDF) as the transmission line, in which the fibre loss is continuously compensated for by the erbium gain, and a nearly lossless transmission line can be realised, removing the constraint on the soliton period. We present our experimental results of 10 GHz and 80 GHz soliton transmission over 60 km Corning DEDF, which, to our knowledge, represents the highest repetition rate soliton transmission through DEDF reported to date