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arXiv · 1206.6256

Ticking terahertz wave generation in attoseconds

Dongwen Zhang·Zhihui Lü·Chao Meng·Xiyu Du·Zhaoyan Zhou·Zengxiu Zhao·Jianmin Yuan
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Abstract

We perform a joint measurement of terahertz waves and high-order harmonics generated from noble atoms driven by a fundamental laser pulse and its second harmonic. By correlating their dependence on the phase-delay of the two pulses, we determine the generation of THz waves in tens of attoseconds precision. Compared with simulations and models, we find that the laser-assisted soft-collision of the electron wave packet with the atomic core plays a key role. It is demonstrated that the rescattering process, being indispensable in HHG processes, dominant THz wave generation as well but in a more elaborate way. The new finding might be helpful for the full characterization of the rescattering dynamics.

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Dongwen Zhang, Zhihui Lü, Chao Meng, Xiyu Du, Zhaoyan Zhou, Zengxiu Zhao, Jianmin Yuan. 2012-06-27. Ticking terahertz wave generation in attoseconds. https://doi.org/10.1103/physrevlett.109.243002

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