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تسجيل مستخدم جديدGeneration of above-TW 1.5-cycle visible pulses at 1 kHz by post-compression in a hollow fiber
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We report on the generation of 6.1 mJ, 3.8 fs pulses by the compression of a kHz Ti:sapphire laser in a large-aperture long hollow fiber. In order to find optimal conditions for spectral broadening at high pulse energies, we explore different parameter ranges where ionization or the Kerr effect dominates. After identifying the optimum parameter settings, large spectral broadening at high waveguide transmission is obtained. The intense 1.5-cycle pulses are used for high-harmonic generation in argon and neon.
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In this work, we demonstrate post-compression of 1.2 picosecond laser pulses to 13 fs via gas-based multi-pass spectral broadening. Our results yield a single-stage compression factor of about 40 at 200 W in-burst average power and a total compressio
n factor >90 at reduced power. The employed scheme represents a route towards compact few-cycle sources driven by industrial-grade Yb:YAG lasers at high average power.
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