Temperature dependence of the gain in erbium-doped fibers

The temperature dependence of the gain in erbium-doped fibers between -20 and +85 degrees C is discussed. The characteristics of three types of erbium-doped fibers with different erbium concentrations and glass compositions are investigated. The gain decreased with increasing temperature at the rate of -0.07 dB/ degrees C when pumped at 1.48 mu m. The change in the gain was small when pumped at 0.98 mu m. By measuring the change in the absorption and fluorescence spectra with temperature, it is deduced that the change in the gain is mainly due to the change in the saturated population inversion.<
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