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arXiv · 1802.09470

Nonlinear dynamics in multimode optical fibers

Stefan Wabnitz·Alessandro Tonello·Vincent Couderc·Daniele Modotto·Alain Barthelemy·Guy Millot·Katarzyna Krupa
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Abstract

We overview recent advances in the research on spatiotemporal beam shaping in nonlinear multimode optical fibers. An intense light beam coupled to a graded index (GRIN) highly multimode fiber undergoes a series of complex nonlinear processes when its power grows larger. Among them, the lowest threshold effect is the Kerr-induced beam self-cleaning, that redistributes most of the beam energy into a robust bell-shaped beam close to the fundamental mode. At higher powers a series of spectral sidebands is generated, thanks to the phase matching induced by the long period grating due to the periodic self-imaging of the beam and the Kerr effect. Subsequently a broadband and spectrally flat supercontinuum is generated, extending from the visible to the mid-infrared.

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Stefan Wabnitz, Alessandro Tonello, Vincent Couderc, Daniele Modotto, Alain Barthelemy, Guy Millot, Katarzyna Krupa. 2018-02-26. Nonlinear dynamics in multimode optical fibers. https://doi.org/10.1117/12.2287874

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