In-fiber measurement of the erbium-doped ZBLAN I-4(13/2) state energy transfer parameter

Erbium-doped ZBLAN (Er:ZBLAN) is a commonly used glass for mid-infrared fiber lasers. Quantifying the energy dynamics of the erbium ions is important for improving the performance of mid-infrared fiber lasers. Previous studies have found a discrepancy between the strength of inter-ion energy transfer measured in bulk Er:ZBLAN and the strength required to explain current fiber laser performance. We have measured the strength of the I-4(13/2) + I-4(13/2) -> I-4(15/2) + I-4(9/2) energy transfer process directly in a range of fibers for the first time, to the best of our knowledge. (C) 2021 Optical Society of America