This paper demonstrates a stable, broad-band two-stage superfluorescent sou
rce at 1.55 mu m consisting of am erbium-doped fiber (EDF) seed source and
a high-power Er-Yb fiber amplifier. The source exhibited from 140 to 220 mW
of power, 18 to 28 nm bandwidth, with an estimated mean wavelength stabili
ty from 1 to 10 ppm. Operating conditions for the seed source and amplifier
required to achieve these performance characteristics are described.