arXiv subjects

Franz Beier

Publications and source records attributed to Franz Beier.

2 recordsLinked to original sources

arXiv2021

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

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.

physics.optics↗

arXiv2021

Experimental Investigations on the TMI Thresholds of Low-NA Yb-doped single mode fibers

In this contribution we investigate the transversal mode instability behavior of an ytterbium doped commercial 20/400 fiber and obtain 2.9 kW of output power after optimizing the influencing parameters. In this context, we evaluate the influence of the bend diameter and the pump wavelength within the scope of the absorption length and the length of the fiber. Furthermore with a newly developed fiber we report on 4.4 kW of single-mode output power at 40 cm bend diameter.

physics.optics↗