Numerical modeling of the induced grating autocorrelation for studying optical fiber nonlinearities in the picosecond regime

摘要

We report a direct numerical model of the induced grating autocorrelation (IGA) based on the numerical solution of the nonlinear Schroedinger equation for an intense optical pulse that has experienced nonlinear distortion [notably, self-phase modulation (SPM) and stimulated Raman scattering (SRS)] after propagating through an optical fiber. Our numerical simulations are in good agreement with experiments. A significant advantage of the numerical approach over the well-known analytical models is its capability to predict IGA traces in the presence of pump depletion. In the light of this, IGA can now be used to study the combined effects of SPM and SRS in optical fibers in the regime where pump depletion is important, and both the nonlinear refractive index and the Raman gain coefficient of the fiber can be extracted.