Midinfrared Pulse Generation by Pumping in the Normal-Dispersion Regime of a Gas-Filled Hollow-Core Fiber

We demonstrate, numerically, the generation of supercontinuum using a high-power ultrafast source at 1.06-mu m wavelength and a nonlinear hollow-core fiber. We yield a system that is less sensitive to noise by pumping in the normal-dispersion regime, yet still achieves enhanced spectral broadening by exciting an optical soliton in the midinfrared region. The pump pulse goes through a series of nonlinear effects leading to a supercontinuum output that spans across the midinfrared, 0.5-4.2 mu m.