Numerical And Experiment Study Of Supercontinuum Based On Special Fiber

The Supercontinuum (SC) spectrum phenomenon in fiber has been conjectured to be the interplay between Group-velocity dispersion (GVD) and fiber nonlinearity, such as self phase modulation, cross phase modulation, stimulated Raman Scattering and Four-Wave Mixing etc.In this thesis, numerical analysis based on Dispersion Flattened Decreasing Fiber (DFDF) and experiment study based on High Non-Linear Fiber (HNLF) of Supercontinuum are introduced. The main contents are as follows:(1) The development and applications of Supercontinuum spectrum are introduced. The basic theory of pulse propagation in fiber is introduced, and also the Nonlinear Schr?dinger equation (NLSE).(2) The physics foundation of the Supercontinuum phenomenon in fiber is discussed, especially those effects in fiber including fiber loss,GVD,TOD and higher-order non-linearity effects such as SPM, SRS, XPM etc. Then some kinds of fiber which are being used for Supercontinuum spectrum generation are introduced.(3)The principle and numerical model of Supercontinuum spectrum generation in the DFDF is presented. Split-Step Fourier methods are used to solve the NLSE in the DFDF, and the generation of Supercontinuum spectrum in the DFDF is simulated numerically. The analysis indicated that the dispersion characteristic of the DFDF fiber is crucial for the Supercontinuum spectrum generation. Also, the effects of the injected pump power,higher-order GVD,higher-order nonlinearity and input pulse chirp are considered.(4)A Supercontinuum spectrum generation experiment using HNLF is demonstrated. A chirp compensation method using SMF is introduced to generate more flattened and wide Supercontinuum spectrum.