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arXiv · 2205.13385

Multimode optical fiber beam-by-beam cleanup

Mario Ferraro·Fabio Mangini·Yann Leventoux·Alessandro Tonello·Mario Zitelli·Yifan Sun·Sebastien Fevrier·Katarzyna Krupa·Denis Kharenko·Stefan Wabnitz·Vincent Couderc
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Abstract

We introduce and experimentally demonstrate the concept of all-optical beam switching in graded-index multimode optical fibers. Nonlinear coupling between orthogonally polarized seed and signal beams permits to control the spatial beam quality at the fiber output. Remarkably, we show that even a weak few-mode control beam may substantially enhance the quality of an intense, highly multimode signal beam. We propose a simple geometrical representation of the beam switching operation, whose validity is quantitatively confirmed by the experimental mode decomposition of the output beam. All-optical switching of multimode beams may find important applications in high-power beam delivery and fiber lasers.

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Mario Ferraro, Fabio Mangini, Yann Leventoux, Alessandro Tonello, Mario Zitelli, Yifan Sun, Sebastien Fevrier, Katarzyna Krupa, Denis Kharenko, Stefan Wabnitz, Vincent Couderc. 2022-05-26. Multimode optical fiber beam-by-beam cleanup. https://doi.org/10.1109/jlt.2023.3239385

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