title: Improved WDM performance of a fibre optical parametric amplifier using Raman-assisted pumping.
abstract: We experimentally demonstrate a Raman-Assisted Fibre Optical Parametric Amplifier (RA-FOPA) with 20dB net gain using wavelength division multiplexed signals. We report amplification of 10x58Gb/s 100GHz-spaced QPSK signals and show that by appropriate tuning of the parametric pump power and frequency, gain improvement of up to 5dB can be achieved for the RA-FOPA compared with combined individual contributions from the parametric and Raman pumps. We compare the RA-FOPA with an equivalent-gain conventional FOPA and find that four-wave mixing crosstalk is substantially reduced by up to 5.8 ± 0.4dB using the RA-FOPA. Worst-case performance penalty of the RA-FOPA is found to be only 1.0 ± 0.2dB over all measured OSNRs, frequencies and input powers, making it an attractive proposal for future communications systems.
authors.forename: M F C
authors.initials: MF
authors.lastname: Stephens
authors.forename: I D
authors.initials: ID
authors.lastname: Phillips
authors.forename: P
authors.initials: P
authors.lastname: Rosa
authors.forename: P
authors.initials: P
authors.lastname: Harper
authors.forename: N J
authors.initials: NJ
authors.lastname: Doran