Study On Nonlinear Raman Scattering Of Toluene Liquid-Core Optical Fiber By Week Light

Nonlinearity of toluene liquid-core optical fiber Raman scattering by weak light was studied in this dissertation. The toluene liquid-core optical fiber Raman scattering experiment under low light conditions was completed. Multi-order Stokes line and Multi-order anti-Stokes lines as well as four-wave mixing phenomenon were observed in the experiments, which shows nonlinear scattering characteristics. Relation between Raman scattering light intensity and the incident light power was studied. Carbon sulfide stimulated Raman scattering and toluene stimulated Raman scattering were studied by experimental method in the dissertation. First-order stimulated Raman spectrum of carbon sulfide second-order stimulated Raman spectrum of carbon sulfide and fourth-order stimulated Raman spectrum of toluene were observed in the experiments. Relation between first-order stimulated Raman spectral intensity of carbon sulfide and the incident power was studied.Compared tow kinds of results each with another it is found that both nonlinear spectra by weak light and stimulated Raman spectra have multi-order scattering spectral lines , under both conditions relation between scattering intensity and power of incident laser is nonlinear. The difference is that nonlinearity by weak light does not have notable threshold. Experiments and their analysis show that under low light condition toluene liquid-core optical fiber Raman scattering has a non-linear characteristic.