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arXiv · 2101.12567

Measuring Thermal Load in Fiber Amplifiers in the Presence of Transversal Mode Instabilities

Franz Beier·Marco Plötner·Bettina Sattler·Fabian Stutzki·Till Walbaum·Andreas Liem·Nicoletta Haarlammert·Thomas Schreiber·Ramona Eberhardt·Andreas Tünnermann
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Abstract

We report on detailed in-situ distributed temperature measurements inside a high power fiber amplifier. The deducted thermal load and the TMI-threshold of a commercial LMA fiber with 25 micron core and 400 micron cladding was measured at various seed wavelengths. By matching these results with detailed simulations we show that photodarkening has a negligible impact on the thermal load and, therefore, on the TMI threshold in this fiber.

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Franz Beier, Marco Plötner, Bettina Sattler, Fabian Stutzki, Till Walbaum, Andreas Liem, Nicoletta Haarlammert, Thomas Schreiber, Ramona Eberhardt, Andreas Tünnermann. 2021-01-29. Measuring Thermal Load in Fiber Amplifiers in the Presence of Transversal Mode Instabilities. https://doi.org/10.1364/ol.42.004311

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