Coherent-Rofin R&D team awarded 'Best Paper' at recent COMSOL Conference

At the COMSOL Conference in Rotterdam (The Netherlands) last November, multi-physics modeling and simulation specialists from across Europe presented their findings in innovative research and modeling work.

Of the over 140 user presentations, the conference program committee recognized three papers that they considered particularly impressive with a special “Best Paper” award.

The presentations at the conference in Rotterdam covered a broad range of topics, including open-cell polyurethane foams, concrete gravity dams and high-power fiber lasers. For the latter topic, the jury gave the “Best Paper” award to Dr. Jens Schüttler, Benjamin Neumann, Steffen Belke, Frank Becker and Dr. Stefan Ruppik from Coherent-ROFIN for their work on Virtual Long Term Testing of High-Power Fiber Lasers.

In recent years, high-power fiber lasers have steadily increased in output power. The scaling to higher powers also produced some challenges, as the effective performance of many fiber lasers can be limited by the effects of photo-darkening and transverse mode instability.

Jens Schüttler and his colleagues developed a special numerical multi-level approach, with very high computational efficiency, in order to track the performance of a fiber laser over its typical lifetime. Their model considers the effects of mode competition, mode energy transfer, laser gain, bend losses, as well as the spatial properties of the actual fiber. The R&D team performed virtual long-term tests with this model by simulating 10,000 hours of laser operation in just a few hours of computation time.

Dr. Schüttler presented his model as guest lecturer in a German language webinar from COMSOL that took place on January 25th, 2018. Interested may attend the webinar at:

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