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arXiv · 2003.03002

Fully stabilized multi-TW optical waveform synthesizer for gigawatt soft-x-ray isolated attosecond pulses

Bing Xue·Yuuki Tamaru·Yuxi Fu·Hua Yuan·Pengfei Lan·Oliver D. Mücke·Akira Suda·Katsumi Midorikawa·Eiji J. Takahashi
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Abstract

A stable 50 mJ three-channel optical waveform synthesizer is demonstrated and used to reproducibly generate a high-order harmonics supercontinuum in the soft-x-ray region. This synthesizer is composed of pump pulses from a 10-Hz-repetition-rate Ti:sapphire pump laser and signal and idler pulses from an infrared two-stage optical parametric amplifier driven by this pump laser. With the full active stabilization of all relative time delays, relative phases, and the carrier-envelope phase, a shot-to-shot stable intense continuum harmonic spectrum is obtained around 60 eV with pulse energy above 0.24 $\mu$J. The peak power of the soft-x-ray continuum is evaluated to be beyond 1 GW with a 140 as transform limit duration. Furthermore, we found a characteristic delay dependence of the multi-cycle waveform synthesizer and established its control scheme. Compared with the one-color case, we experimentally observe an enhancement of the cut-off spectrum intensity by one to two orders of magnitude through the three-color waveform synthesis.

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Bing Xue, Yuuki Tamaru, Yuxi Fu, Hua Yuan, Pengfei Lan, Oliver D. Mücke, Akira Suda, Katsumi Midorikawa, Eiji J. Takahashi. 2020-03-06. Fully stabilized multi-TW optical waveform synthesizer for gigawatt soft-x-ray isolated attosecond pulses. https://doi.org/10.1126/sciadv.aay2802

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