Experimental demonstration of time-division multiplexed Raman pumping

Using a time-division multiplexed, frequency-swept Raman pump configuration, we were able to dynamically flatten the on/off Raman gain of a 15 km long telecommunications fiber. We achieved a gain ripple of 0.6 dB over a range of 15 nm with a single, tunable laser as the Raman pump source. The limitation on the bandwidth that could be flattened is only caused by the high-power erbium-doped fiber amplifier employed to generate enough Raman pump power in the present design.