Coherence evolution of multi-pulse pumped supercontinuum generation in all-normal dispersion fibers.

We numerically calculate the coherence of supercontinuum (SC) spectrum generated in all-normal dispersion (ANDi) fibers by multiple picosecond pulses. We show that multi-pulse pumping significantly mitigates the phenomenon of coherence degradation and maintains high spectral coherence over a broader wavelength range compared to the single pumping. It is found that inter-pulse four-wave-mixing (FWM) and stimulated Raman scattering (SRS) significantly contribute to the superior coherence characteristics of the SC.