Weak beam self-cleaning of femtosecond pulses in the anomalous dispersion regime

Kerr beam cleaning in graded-index multimode fiber has been investigated in experiments with sub-nanosecond pulses and in experiments with femtosecond pulses at wavelengths where the dispersion is normal. We report a theoretical and experimental study of this effect with femtosecond pulses and anomalous dispersion. In this regime, only weak beam cleaning is observed experimentally, along with strong temporal evolution of the pulse. Numerical simulations exhibit the qualitative trends of the experiments. (C) 2021 Optical Society of America

Automated summary

Experiments were conducted on Kerr beam cleaning in graded-index multimode fiber with sub-nanosecond and femtosecond pulses at wavelengths characterized by normal dispersion. Weak beam cleaning was observed experimentally, with strong temporal evolution of the pulse. Numerical simulations qualitatively matched the experimental trends.