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arXiv · 1805.12127

Terahertz generation in dual-color laser: continuum electron in strong-field single-atom ionization

Kaixuan Zhang·Yizhu Zhang·T. -M. Yan·Y. H. Jiang
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Abstract

The terahertz (THz) generation in a dual-color field was investigated experimentally by precisely controlling the relative time delay $τ$ and polarization $θ$ of dual-color lasers, where the accompanying third-harmonic generation (THG) is employed to determine $τ$ up to the sub-wavelength accuracy. An anticorrelation of the yields between THz and THG with $τ$ was displayed. Compared with the theoretical simulations, the experimental results reveal that the continuum-continuum transitions of the released electron after single-atom ionization are the dominating mechanism for THz generation, which is opposite to the high-harmonic generation (HHG) based on the recollision mechanism, or the radiation induced by perturbative bound-bound transitions.

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Kaixuan Zhang, Yizhu Zhang, T. -M. Yan, Y. H. Jiang. 2018-05-30. Terahertz generation in dual-color laser: continuum electron in strong-field single-atom ionization. https://doi.org/10.1364/prj.377408

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