Numerical analysis of beam self-cleaning in multimodefiber amplifiers

  title={Numerical analysis of beam self-cleaning in multimodefiber amplifiers},
  author={Mesay Addisu Jima and Alessandro Tonello and Alioune Niang and Tigran Mansuryan and Katarzyna Krupa and Daniele Modotto and Annamaria Cucinotta and Vincent Couderc and Stefan Wabnitz},
  journal={Journal of the Optical Society of America B},
Recent experimental results have reported the observation of beam self-cleaning or, more generally, nonlinear beam reshaping in active multimode fibers. In this work we present a numerical analysis of these processes, by considering the ideal case of a diode-pumped signal amplifier made of a graded-index multimode fiber with uniform Yb doping. Simulations confirm that beam cleaning of the signal may take place even in amplifying fibers, that is the absence of beam energy conservation. Moreover, we… 



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