Supercontinuum generation by stimulated Raman-Kerr scattering in a liquid-core optical fiber

We investigate nonlinear picosecond pulse propagation at 532 nm in an optical fiber capillary filled with toluene liquid and demonstrate supercontinuum generation from 550 nm up to 870 nm. Although it operates in the strong normal dispersion regime, we show that supercontinuum light is generated through the combined effects of multiple cascaded Raman scattering and stimulated Raman-Kerr scattering, which enables a large spectral broadening of the Raman lines owing to the strongly anisotropic orientational relaxation of liquid molecules. We further present numerical simulations of the nonlinear Schrodinger equation, including the Raman scattering, to show the spectro-temporal dynamics. (C) 2017 Optical Society of America