Supercontinuum growth in a highly nonlinear fiber with a low-coherence semiconductor laser diode

A low-coherence, amplified, cw semiconductor laser diode is used as a pump to demonstrate supercontinuum (SC) generation in a highly nonlinear, dispersion-shifted fiber (HNLF). At a launch power of 1.6 W into the anomalous-dispersion regime of 5 km of HNLF, a SC extending from 1230 nm to greater than 1770 nm is achieved. The SC grows through the seeding effect of modulation instability that also converts the cw beam into short pulses so that subsequent spectral broadening becomes similar to pumping with pulsed laser sources. The experimental data show the manifestation of soliton self-frequency shift associated with a Stokes band as the launch power is increased. Amplification of the continuum noise with respect to the cw pump is also reported. (C) 2004 American Institute of Physics.