Coherent supercontinuum in a silicate glass composite fiber with all-normal dispersion

With all-normal-dispersion fibers, highly coherent supercontinuum (SC) can be obtained, which has several applications. Traditional air-hole photonic crystal fibers encountered some limitations for such light emission. In this study, all solid composite fibers with a silica glass cladding and a yttria-alumino-silicate glass core were fabricated, which were designed for flat coherent SCs. We achieved a flat normal dispersion in this composite fiber. Flat SCs were experimentally demonstrated with different pump conditions. The simulated SC spectra coincided well with the experimental results. It also indicated that a coherent SC with more than one octave can be obtained with higher input power.