Effect Of Raman Gain On The Self-steeping Characteristic In Isotropic Fiber

With the rapid development of technology, people continue deepening the study of nonlinear optics. Optical pulses in optical fibers have exhibited more self-steepening effect in which caused widespread concern in academic research, the self-steepening effect has gradually become an important branch of nonlinear optics. The self-steepening effect is a significant nonlinear effects of light pulse propagation in isotropic fibers. It is based on the optical pulse group velocity be dependencies on light intensity. The self-steepening effect of light have a strong influence on the intensity of the light pulse、the pulse broadening、the pulse shape and the pulse peak excursion. This paper have studied how Raman gain affects on the self-steepening of light pulses under conditions of ignoring fiber loss in the isotropic fiber. The text is broadly divided into three parts:first, the Raman scattering have detailed introduced and the nonlinear schrodinger equation under the condition of considering Raman gain have deduced; second, the Gauss pulse as an example, self-steepening effect of Gaussian pulse under different conditions is analyzed and calculated by mathematics analytic method and numerical simulation method. The MATLAB is used to simulate the image from the self-steepening effects of Gaussian pulse; finally, the self-steepening effect of the Gaussian pulse chart have comprehensive analyzed, the result have showed that Raman gain how to affects the self-steepening effect of Gaussian pulse. In this process, the Schrodinger equation contains the Raman gain have derived,Simultaneously the Raman gain influence on the self-steepening effect of Gaussian pulse have studied under the condition ignoring the dispersion. The new analytical research method-mathematical analytic method have used in which allows a more accurate conclusion.