Ge-Doped microstructured multicorefiber for customizable supercontinuum generation

Supercontinuum generation in a multicore fiber in which several uncoupled cores
were doped with dissimilar concentrations of germanium was studied experimentally.
Germanium doping provided control over the separation between the zero-dispersion
wavelength and the 1064-nm wavelength of a Q-switched Nd:YAG pump laser. Supercontinua
generated independently in each core of the same piece of fiber displayed clear
and repeatable differences due to the influence of germanium doping on refractive index and
four-wave mixing. The spectral evolution of the subnanosecond pump pulses injected into
the different cores was accurately reproduced by numerical simulations.