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arXiv · 1603.02972

Spatial beam self-cleaning in multimode fiber

Katarzyna Krupa·Alessandro Tonello·Badr M. Shalaby·Marc Fabert·Alain Barthélémy·Guy Millot·Stefan Wabnitz·Vincent Couderc
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Abstract

Multimode optical fibres are enjoying a renewed attention, boosted by the urgent need to overcome the current capacity crunch of single-mode fibre systems and by recent advances in multimode complex nonlinear optics [1-13]. In this work, we demonstrate that standard multimode fibres can be used as ultrafast all-optical tool for transverse beam manipulation of high power laser pulses. Our experimental data show that the Kerr effect in a graded-index multimode fibre is the driving mechanism for overcoming speckle distortions, leading to a somewhat counter-intuitive effect resulting in a spatially clean output beam robust against fibre bending. Our observations demonstrate that nonlinear beam reshaping into the fundamental mode of a multimode fibre can be achieved even in the absence of a dissipative process such as stimulated scattering (Raman or Brillouin) [14,15].

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Katarzyna Krupa, Alessandro Tonello, Badr M. Shalaby, Marc Fabert, Alain Barthélémy, Guy Millot, Stefan Wabnitz, Vincent Couderc. 2016-03-09. Spatial beam self-cleaning in multimode fiber. https://doi.org/10.1038/nphoton.2017.32

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