A 105-nm ultrawide-band gain-flattened amplifier combining C- and L-band dual-core EDFAs in a parallel configuration

A novel structure for ultrawide-band gain-flattened amplifier by combining two pieces of C- and L-band dual-core erbium-doped fibers is reported. This novel amplifier has a flat gain of 15 dB over a wavelength range of 105 nm (1515-1620 nm). The gain variation for the C-band flat gain region (1515-1555 nm) is 1.3 dB, and for the L-band flat gain region (1562-1620 nm) is 1.5 dB. The noise figure varies from 4.5 to 4.8 dB over the whole bandwidth. The structure of the design is simple without the need of additional expensive components.