TY - JOUR

T1 - Coherent combining of self-cleaned multimode beams

AU - Fabert, Marc

AU - Săpânțan, Maria

AU - Krupa, Katarzyna

AU - Tonello, Alessandro

AU - Leventoux, Yann

AU - Février, Sébastien

AU - Mansuryan, Tigran

AU - Niang, Alioune

AU - Wetzel, Benjamin

AU - Millot, Guy

AU - Wabnitz, Stefan

AU - Couderc, Vincent

N1 - Funding Information: M.F., M.S., A.T., and V.C. acknowledge the financial support provided by: the French ANR through the “TRAFIC project: ANR-18-CE080016-01”; the CILAS Company (ArianeGroup) through the shared X-LAS laboratory; the “Région Nouvelle Aquitaine” through the projects F2MH, SIP2 and Nematum; the National Research Agency under the Investments for the future program with the reference ANR-10-LABX-0074-01 Sigma-LIM. K.K. acknowledges the European Union’s Horizon 2020 research and innovation programme under the Marie-Skłodowska-Curie (No. 713694); S.W. acknowledges the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (No. 740355), and the Russian Ministry of Science and Education (Grant 14.Y26.31.0017); G.M. acknowledges the Conseil Régional de Bourgogne Franche-Comté, the iXcore research foundation and the National Research Agency (ANR-15-IDEX-0003, ANR-17-EURE-0002). Publisher Copyright: © 2020, The Author(s). Copyright: Copyright 2020 Elsevier B.V., All rights reserved.

PY - 2020/12

Y1 - 2020/12

N2 - A low intensity light beam emerges from a graded-index, highly multimode optical fibre with a speckled shape, while at higher intensity the Kerr nonlinearity may induce a spontaneous spatial self-cleaning of the beam. Here, we reveal that we can generate two self-cleaned beams with a mutual coherence large enough to produce a clear stable fringe pattern at the output of a nonlinear interferometer. The two beams are pumped by the same input laser, yet are self-cleaned into independent multimode fibres. We thus prove that the self-cleaning mechanism preserves the beams’ mutual coherence via a noise-free parametric process. While directly related to the initial pump coherence, the emergence of nonlinear spatial coherence is achieved without additional noise, even for self-cleaning obtained on different modes, and in spite of the fibre structural disorder originating from intrinsic imperfections or external perturbations. Our discovery may impact theoretical approaches on wave condensation, and open new opportunities for coherent beam combining.

AB - A low intensity light beam emerges from a graded-index, highly multimode optical fibre with a speckled shape, while at higher intensity the Kerr nonlinearity may induce a spontaneous spatial self-cleaning of the beam. Here, we reveal that we can generate two self-cleaned beams with a mutual coherence large enough to produce a clear stable fringe pattern at the output of a nonlinear interferometer. The two beams are pumped by the same input laser, yet are self-cleaned into independent multimode fibres. We thus prove that the self-cleaning mechanism preserves the beams’ mutual coherence via a noise-free parametric process. While directly related to the initial pump coherence, the emergence of nonlinear spatial coherence is achieved without additional noise, even for self-cleaning obtained on different modes, and in spite of the fibre structural disorder originating from intrinsic imperfections or external perturbations. Our discovery may impact theoretical approaches on wave condensation, and open new opportunities for coherent beam combining.

KW - FIBER

KW - SCATTERING

KW - MODE

UR - http://www.scopus.com/inward/record.url?scp=85096557724&partnerID=8YFLogxK

U2 - 10.1038/s41598-020-77505-0

DO - 10.1038/s41598-020-77505-0

M3 - Article

C2 - 33235274

AN - SCOPUS:85096557724

VL - 10

SP - 20481

JO - Scientific Reports

JF - Scientific Reports

SN - 2045-2322

IS - 1

M1 - 20481

ER -