Pulse generation in birefringent fibers by four-wave mixing in the presence of Raman scattering is theoretically modeled by a set of coupled nonlinear Schrödinger equations that are solved numerically. We discuss phase matching in the positive group-velocity dispersion regime for the split-pump configuration, which places the parametric frequency shift within the Raman band, and derive the combined initial gain. It is found that for shorter fiber lengths the symmetry-breaking roles of Raman–Stokes gain and Raman–anti-Stokes loss is balanced by four-wave mixing, resulting in a common effective power gain for both components. The importance of the relative phase of the four participating pulses as a switching parameter for the direction of the energy flow is demonstrated. It is further shown that, as a result of pulse walk-off, Raman scattering becomes the dominant process for longer fiber lengths. Theoretical results are compared with experimental cross-correlation pulse shapes.
© 1995 Optical Society of AmericaFull Article | PDF Article
OSA Recommended Articles
P. Tchofo Dinda, G. Millot, and S. Wabnitz
J. Opt. Soc. Am. B 15(5) 1433-1441 (1998)
Opt. Lett. 26(18) 1391-1393 (2001)
Frédérique Vanholsbeeck, Philippe Emplit, and Stéphane Coen
Opt. Lett. 28(20) 1960-1962 (2003)