High Gain, Low Noise, Spectral-Gain-Controlled, Broadband Lumped Fiber Raman Amplifier

We demonstrate an 80 nm bandwidth (extending from 1529 to 1609 nm), dual-stage, diode-pumped, lumped Raman amplifier using a relatively short total length (2 km) of highly nonlinear fiber. The impact of Rayleigh back scattering is mitigated and the build-up of thermally generated wavelength dependent noise is controlled by suitably adjusting the spectral gain profile in the two amplifier stages. In this way a high overall gain of 27 dB with 2.6 dB gain flatness and an average noise figure of 5.8 dB with <1 dB variation is achieved across the full amplifier bandwidth.

Automated summary

An 80 nm bandwidth dual-stage diode-pumped lumped Raman amplifier with a short length of highly nonlinear fiber is demonstrated, achieving a high overall gain of 27 dB. By adjusting the spectral gain profile in the two amplifier stages, Rayleigh back scattering impact is mitigated and thermally generated noise is controlled, resulting in an average noise figure of 5.8 dB with <1 dB variation across the full amplifier bandwidth.