title: Quasi-stationary multiple stimulated Raman generation in the visible using optical fibers.
abstract: Several orders of stimulated Raman scattering (SRS) in monomode and multimode fibers have been observed. The relatively low power in the visible used in the quasi-stationary regime permitted observation of sharply defined Stokes and anti-Stokes spectral lines without any continua. Results of pump-to-Stokes power conversion in a monomode fiber indicate a striking equivalence between pump power and fiber length. The dependence of multiple SRS generation/amplification with these parameters is investigated up to the limit of near total pump extinction. We propose a qualitative explanation of these facts, although a detailed theory of nonlinear behavior of fibers is wanting. Parametric four-photon mixing is again confirmed to account for the generation of stimulated anti-Stokes radiation in multimode fibers and its absolute absence in monomode fibers.
authors.affiliation: TELEBRAS, Centro de Pesquisa e Desenvolvimento, Caixa Postal 1579, Campinas 13.100, SP Brazil.
authors.forename: F R
authors.initials: FR
authors.lastname: Barbosa