Detrimental effects in four wave mixing

Four wave mixing (FWM) holds great promise as a tool to perform signal processing of classical light as well as of quantum states. However, typically FWM require use of high power pumps and as a consequence, the FWM process is accompanied by spontaneous Raman scattering as well as spontaneous FWM. In addition, FWM is also very sensitive to changes in the phase matching along propagation, caused by fluctuations in the core geometry of the fiber. In this work, we review recent progress in predicting and measuring the conversion efficiency and noise figure of wavelength conversion using FWM and we show consequences due fluctuations in the core geometry.