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arXiv · 2508.06268

High contrast few-cycle frontend with hybrid amplification for petawatt-class lasers

Roland S. Nagymihály·Mikhail Kalashnikov·Levente Lehotai·Viktor Pajer·János Bohus·Nóra Csernus-Lukács·János Csontos·Szabolcs Tóth·Balázs Tari·Ignas Balciunas·Ernestas Kucinskas·Tomas Stanislauskas·Ádám Börzsönyi
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Abstract

We present a 10 mJ-class laser system for seeding petawatt-class Ti:Sa lasers based on a hybrid, femtosecond optical parametric and negatively chirped Ti:Sa-based amplification architecture. Output pulses with 13 mJ energy, 14.4 fs transform limited duration, and high spatio-spectral quality are reached at 100 Hz repetition rate centered at 788 nm wavelength. By compressing 1 mJ energy with bulk glass and positively chirped mirrors, a pulse duration of 15.5 fs is measured. The intensity contrast is higher than 10$^{12}$ already 15 ps before the main pulse. The presented architecture can be a robust and reliable solution for seeding sub-17 fs high intensity lasers with ultrahigh contrast at up to 100 Hz repetition rate.

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Roland S. Nagymihály, Mikhail Kalashnikov, Levente Lehotai, Viktor Pajer, János Bohus, Nóra Csernus-Lukács, János Csontos, Szabolcs Tóth, Balázs Tari, Ignas Balciunas, Ernestas Kucinskas, Tomas Stanislauskas, Ádám Börzsönyi. 2025-08-08. High contrast few-cycle frontend with hybrid amplification for petawatt-class lasers. https://arxiv.org/abs/2508.06268

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