Raman-generated pump impact on optical parametric amplification

Continuous-wave (CW) Raman-generated pump impact on a fiber optical parametric amplifier (OPA) is analyzed. Different noise contributions associated to the pump are experimentally and theoretically evaluated. Gain and noise figure of the amplifier are presented and commented for different OPA configurations. By tightly filtering the CW Raman-generated pump an OPA noise figure approaching the 3 dB limit is achieved.