Pump-probe investigation of cross-phase modulation in standard-fibre, dispersion compensated WDM recirculating loop

Summary form only given. Increased inter-amplifier distances in future WDM systems will require high optical power resulting in signal distortion due to fibre nonlinearity. Only little work has been done investigating the dependence of cross-phase modulation (XPM) on system parameters such as transmission distance, channel wavelength spacing and residual dispersion. In multi-span dispersion compensated standard single-mode fibre links (SSMF, D=17 ps/nm/km) in which the dispersion compensating fibre (DCF) is positioned at the end of each span, the transmission distance is limited by self-phase modulation (SPM), which rapidly broadens the pulses. We show experimentally that positive residual dispersion can be used to counteract this broadening, and that this technique can effectively reduce intensity distortion due to XPM.