Nonresonant spectral-hole burning in erbium-doped fiber amplifiers

We report here, for the first time, observations of offset and collaterally burned holes in erbium-doped fiber amplifiers (EDFAs). This additional spectral-hole-burning structure in the 1.5-μm region will impact the application of EDFAs in the wavelength-division-multiplexed environment as well as their descriptive models.