Spectral hole burning induced by reflected amplified spontaneous emission in erbium-doped silica optical fiber pumped at 980 nm

We applied an erbrium-doped fiber amplifier characterization method previously reported for 1480-nm pumped amplifiers to a 980-nm amplifier, obtaining absorption and emission coefficients, as well as the dopant concentration in fiber. Gain and fluorescence (amplified spontaneous emission) simulations performed from the obtained features agree well with experimental results. Nevertheless, at certain high-gain circumstances, disagreements appear in the form of spectral hole burning, which can present high magnitudes and whose nature is discussed. (C) 2003 Optical Society of America.