<title>Mutual effects of stimulated Raman scattering and four-wave mixing in phosphosilicate fibers</title>

ABSTRACT The mutual effects of stimulated Raman scattering and four-wave mixing(FWM) in phosphosilicate fibers is studied experimentally and theoretically. It is found that the output spectra depend on the launched condition strongly.When only one mode is excited in the fiber, the output spectrum is determined by the competition of stimulated Raman scattering between the Si02 and P2 05 . The Si02 Raman line is dominative with lower pump power or using of short length fiber. While the pump power is increased or the long fiber is used, the P205 Raman line increased and the Si02 Raman line is suppressed. When two modes are excited in the fiber, the effects of four-wave mixing is dominative and the spectrum only consist of lines of FMW-assisted Raman scattering of Si02.Keywords: Nonlinear Optical Fiber, Stimulated Raman Scattering, Fiber Raman Laser 1. INTRODUCTION Nonlinear effects in optical fibers, in particular, stimulated Raman scattering (SRS) and its applications for thedevelopment of fiber Raman lasers, have been investigated extensively."2 In most of these researches, attentionsare paid on pure silica fibers for its widely applications in the communication. Recently, P205-doped silica (phos-phosilicate or P-doped) fiber attracted much interest for its high Raman shift,3 which is about three times of that