By pumping a fiber in the anomalous group-velocity-dispersion regime with a color-center laser we generate pulses with τ ≳ 100 fsec covering a wide spectral range of 1.55 µm < λ < 1.85 µm. Cross-correlation measurements show the lack of correlation between different parts of the spectrum. Computer simulations show that modulation instability and the soliton self-frequency-shift effect initiate a multisoliton collision process that results in narrow, high-intensity, fundamental solitons. The observed broad spectra correspond to an ensemble average over these solitons, which start from noise and frequency shift by different amounts.
© 1989 Optical Society of America
M. N. Islam, G. Sucha, I. Bar-Joseph, M. Wegener, J. P. Gordon, and D. S. Chemla, "Broad bandwidths from frequency-shifting solitons in fibers," Opt. Lett. 14, 370-372 (1989)