Paper 14092-21
Paper 14092-21
Ultrafast nonlinear fiber amplifier in the 1560-1670nm spectral range optimized with machine learning
14 April 2026 • 11:40 - 12:00 CEST | Churchill (Niveau/Level 1)
Abstract
We demonstrate the generation of ultrashort pulses in a fiber amplifier covering the L (1560-1625 nm) and U (1625–1675 nm) telecommunication bands by utilizing nonlinear effects and machine learning algorithms. The research details the development and optimization of an ultrafast nonlinear fiber amplifier based on Erbium-Ytterbium co-doped, small-core (3.8 μm) double-clad fiber. This fiber design enables amplification in the normal dispersion regime, which is typically unavailable in this spectral range, and increases sensitivity to nonlinear effects. The setup allows us to produce a broadband output spectrum through nonlinear effects and the characteristic redshift of the normal dispersion regime. A programmable optical filter is placed at the amplifier input, allowing control over the spectral phase and shape of the initial pulse. Machine learning algorithms are used to iteratively modify the input pulse and evaluate the output to achieve the most optimal results.
Presenter
Mikołaj Krakowski
Politechnika Wrocławska (Poland)
Assistant researcher in the Field Theory, Electronic Circuits, and Optoelectronics department, led by Prof. Jarosław Sotor. His main expertise lies in ultrafast fiber lasers and nonlinear fiber amplifiers. He has worked on implementing NALM fiber oscillators with thulium-doped fiber, achieving a central wavelength of 1985 nm. Recently, he shifted his focus to developing and controlling nonlinear fiber amplifiers with spectral-phase modulation of input pulses and applying machine learning algorithms. The first system shortened pulse lengths from 46 fs to 36 fs and reduced side-pulse intensity by 4.6 times. Recently, he demonstrated the first gain-managed nonlinear amplifier in erbium-doped fiber, delivering ultrashort pulses in the 1560-1610 nm spectral range. These results earned him the "Editor's Pick" award from Optics Express and paved the way for the research he will present today. Currently, he is completing his PhD under the supervision of Prof. Grzegorz Soboń.