Modified Raman Response Model and Supercontinuum Generation in Flat Dispersion Photonic Crystal Fiber with Two-Zero Dispersion Wavelengths

Abstract

The generation mechanisms of supercontinuum (SC) and the effect of the modified Raman model on SC are further analyzed in a flat dispersion photonic crystal fiber (PCF) with two-zero dispersion wavelengths (TZDWs) by introducing an accurate Raman response function in the scalar nonlinear Schrödinger equation. The results show that the introduction of Boson peak in the modified Raman gain model not only results in much rapider broadening of SC but also promotes more pump pulse energy transferred to the short wavelength region, which is related to stimulated Raman scattering. Moreover, SC generated from the PCF splits into two spectral bands, and their spectral peaks rapidly separate and broaden with the increase of incident power. Double-band central wavelengths are finally located at about 850 nm and 1220 nm. The pumping energy depletion phenomenon occurs. The simulated results from the modified Raman model are in better agreement with the experimental results than that from the single-Lorentzian model.