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arXiv · 2101.08499

3.5 kW coherently combined ultrafast fiber laser

Michael Müller·Arno Klenke·Albrecht Steinkopff·Henning Stark·Andreas Tünnermann·Jens Limpert
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Abstract

An ultrafast laser based on coherent beam combination of four ytterbium-doped step-index fiber amplifiers is presented. The system delivers an average power of 3.5 kW and a pulse duration of 430 fs at 80 MHz repetition rate. The beam quality is excellent (M2<1.24x1.10) and the relative intensity noise is as low as 1% in the frequency span from 1 Hz to 1 MHz. The system is turn-key operable as it features an automated spatial and temporal alignment of the interferometric amplification channels.

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Michael Müller, Arno Klenke, Albrecht Steinkopff, Henning Stark, Andreas Tünnermann, Jens Limpert. 2021-01-21. 3.5 kW coherently combined ultrafast fiber laser. https://doi.org/10.1364/ol.43.006037

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