Shaping the light amplified in a multimode fiber.

Autor: Florentin R; XLIM Research Institute, Université de Limoges-Centre National de la Recherche Scientifique, UMR 6252, 87060 Limoges, France., Kermene V; XLIM Research Institute, Université de Limoges-Centre National de la Recherche Scientifique, UMR 6252, 87060 Limoges, France., Benoist J; XLIM Research Institute, Université de Limoges-Centre National de la Recherche Scientifique, UMR 6252, 87060 Limoges, France., Desfarges-Berthelemot A; XLIM Research Institute, Université de Limoges-Centre National de la Recherche Scientifique, UMR 6252, 87060 Limoges, France., Pagnoux D; XLIM Research Institute, Université de Limoges-Centre National de la Recherche Scientifique, UMR 6252, 87060 Limoges, France., Barthélémy A; XLIM Research Institute, Université de Limoges-Centre National de la Recherche Scientifique, UMR 6252, 87060 Limoges, France., Huignard JP; Institut Langevin, ESPCI-ParisTech, 75238 Paris, France.
Jazyk: angličtina
Zdroj: Light, science & applications [Light Sci Appl] 2017 Feb 24; Vol. 6 (2), pp. e16208. Date of Electronic Publication: 2017 Feb 24 (Print Publication: 2017).
DOI: 10.1038/lsa.2016.208
Abstrakt: Propagation of light in multimode optical fibers usually gives a spatial and temporal randomization of the transmitted field similar to the propagation through scattering media. Randomization still applies when scattering or multimode propagation occurs in gain media. We demonstrate that appropriate structuration of the input beam wavefront can shape the light amplified by a rare-earth-doped multimode fiber. Profiling of the wavefront was achieved by a deformable mirror in combination with an iterative optimization process. We present experimental results and simulations showing the shaping of a single sharp spot at different places in the output cross-section of an ytterbium-doped fiber amplifier. Cleaning and narrowing of the amplifier far-field pattern was realized as well. Tailoring the wavefront to shape the amplified light can also serve to improve the effective gain. The shaping approach still works under gain saturation, showing the robustness of the method. Modeling and experiments attest that the shaping is effective even with a highly multimode fiber amplifier carrying up to 127 modes.
Competing Interests: The authors declare no conflict of interest.
Databáze: MEDLINE