Amplifier/Compressor Fiber Raman Lasers.

We show that the chirp from cross-phase-modulation (XPM) dominates the operation of fiber Raman lasers (FRL). Thus an FRL in the anomalous group velocity regime is best described as an XPM-chirped Raman amplifier followed by a linear fiber compressor. While the output of such a laser is generally a narrow pulse with a broad pedestal, we show both experimentally and by computer simulation that negligible background is achievable.