Non-Linear Spectral Broadening Across Multiple Bandgaps of All Solid Photonic Crystal Fibers

Nonlinear spectral broadening in two dimensional solid core photonic bandgap fibers is numerically investigated in the anomalous dispersion regime. A frequency-domain approach is used to simulate supercontinuum generation when femtosecond pulses are launched into a transmission band of a typical structure. The consequences on the output characteristics of the strong frequency dependence of the nonlinear parameter, the dispersion and the confinement losses of this kind of micro-structured fiber are highlighted, and we point out the necessity to include all of them in any numerical modeling of experiments. This numerical approach allows us to consider also the propagation of field energy in multiple photonic bandgaps simultaneously, and we show that efficient nonlinear spectral energy transfer is possible between adjacent and several photonic bandgaps across spectral regions of high attenuation.