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arXiv · 2211.10241

Spectral broadening in convex-concave multipass cells

Kilian Fritsch·Victor Hariton·Kevin Schwarz·Nazar Kovalenko·Goncalo Figueira·Oleg Pronin
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Abstract

Since its first demonstration in 2016, the multi-pass spectral broadening technique has covered impressive ranges of pulse energy (3 $\mu$J - 100 mJ) and peak power (4 MW - 100 GW). Energy scaling of this technique into the joule-level is currently limited by phenomena such as optical damage, gas ionization and spatio-spectral beam inhomogeneity. These limitations can be overcome by the novel multi-pass convex-concave arrangement, which exhibits crucial properties such as large mode size and compactness. In a proof-of-principle experiment, 260 fs, 15 $\mu$J and 200 $\mu$J pulses are broadened and subsequently compressed to approximately 50 fs with 90 % efficiency and excellent spatio-spectral homogeneity across the beam profile.

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Kilian Fritsch, Victor Hariton, Kevin Schwarz, Nazar Kovalenko, Goncalo Figueira, Oleg Pronin. 2022-11-18. Spectral broadening in convex-concave multipass cells. https://arxiv.org/abs/2211.10241

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