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Multi-wavelength erbium-doped fiber laser based on four-wave mixing

We propose and report on a novel multi-wavelength erbium-doped fiber laser (EDFL) on the basis of cascading of fiber Bragg gratings (FBGs) and four-wave mixing (FWM) effect in a highly nonlinear fiber (HNLF). A 1-km HNLF is incorporated in the laser cavity to eliminate the strong gain competitions in the homogeneously broadened erbium-doped fiber (EDF) by the degenerate FWM processes. Stable laser pulses at 1556.55, 1557.36, 1558.17, and 1558.98 nm are successfully obtained simultaneously and the spectrum is stabilized and the uniformity is less than 0.6dB.