Blue-enhanced Supercontinuum Generation in a Fluorine-doped Graded-index Multimode Fiber

Blue-enhanced, broadband supercontinuum generation in a 50 um core fluorine-doped graded-index multimode fiber is demonstrated by pumping with a 1064 nm picosecond source. Multi-octave supercontinuum spectrum extending from ~400 nm to 2,400 nm is achieved in a relatively short fiber. The measured spectrum and multimode nonlinear properties are compared to those of a germanium-doped graded-index multimode fiber. It is shown that engineering the glass composition and thus its chromatic dispersion and absorption characteristics, provides a novel and effective approach to further controlling the nonlinear dynamics in highly multimoded parabolic-index fibers.