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arXiv · 2207.11516

8.7-W average power, in-band pumped femtosecond Ho:CALGO laser at 2.1 um

Weichao Yao·Yicheng Wang·Sergei Tomilov·Martin Hoffmann·Sharhwar Ahmed·Christoph Liebald·Daniel Rytz·Mark Peltz·Volker Wesemann·Clara J. Saraceno
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Abstract

We report on an in-band pumped SESAM mode-locked Ho:CALGO bulk laser with a record-high average power of 8.7 W and an optical-to-optical efficiency of 38.2% at a central wavelength of 2.1 um. At this power level, the bulk laser generates pulses with a duration of 369 fs at 84.4-MHz repetition rate, corresponding to a pulse energy of 103 nJ and a peak power of 246 kW. To the best of our knowledge, this is the highest average power and pulse energy directly generated from a mode-locked bulk laser in the 2-3 um wavelength region. Our current results indicate that Ho:CALGO is a competitive candidate for average power scaling of 2 um femtosecond lasers.

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Weichao Yao, Yicheng Wang, Sergei Tomilov, Martin Hoffmann, Sharhwar Ahmed, Christoph Liebald, Daniel Rytz, Mark Peltz, Volker Wesemann, Clara J. Saraceno. 2022-07-23. 8.7-W average power, in-band pumped femtosecond Ho:CALGO laser at 2.1 um. https://doi.org/10.1364/oe.471341

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