4 Gb/s soliton data transmission over 136 km using erbium doped fiber amplifiers

The use of semiconductor-laser-pumped erbium-doped fiber amplifiers and an externally modulated mode-locked external-cavity semiconductor laser to obtain soliton data transmission at 4 Gb/s over 136 km of nondispersion shifted fiber is described. After 136 km of transmission and at low pulse powers, the approximately 80 ps fiber input pulse width was broadened to approximately 150 ps. At high pulse powers the output pulse width was maintained at 80 ps, as expected for N=1 solitons. N=3 solitons were also observed at lower data rates.<
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