A new technique is proposed to simultaneously amplify signals and equalize power unbalance caused by Raman-induced crosstalk among optical channels in the 1.3-μm band. The crosstalk is induced in GeO2-doped silica fibers due to the Raman-gain coefficient with a positive slope below the peakfrequency shift of 440 cm-1. Highly doped GeO2 silica fiber, however, shows a negative slope across the band between 440 cm-1 and 490 cm-1. We propose expansion of the Raman-gain band with a negative slope over the bandwidth of 150 cm-1 using multiple pumps. Utilizing the negative gain slope of the proposed band, simultaneous amplification and power equalization was theoretically demonstrated for 30 channels in the 1.310-1.345 μm region without external filters.
All Science Journal Classification (ASJC) codes
- Atomic and Molecular Physics, and Optics