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Unveiling temporal correlations characteristic to phase transition in the intensity of a fibre laser radiation

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 نشر من قبل Andr\\'es Aragoneses
 تاريخ النشر 2015
  مجال البحث فيزياء
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We use advanced statistical tools of time-series analysis to characterize the dynamical complexity of the transition to optical wave turbulence in a fibre laser. Ordinal analysis and the horizontal visibility graph applied to the experimentally measured laser output intensity reveal the presence of temporal correlations during the transition from the laminar to the turbulent lasing regimes. Both methods unveil coherent structures with well defined time-scales and strong correlations both, in the timing of the laser pulses and in their peak intensities. Our approach is generic and may be used in other complex systems that undergo similar transitions involving the generation of extreme fluctuations.

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