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arXiv · 2406.03854

Universal properties of locally generated terahertz waveforms from polarization-controlled two- and multi-color ionizing fields

H. Alirezaee·S. Skupin·V. Vaicaitis·A. Demircan·I. Babushkin·Luc Bergé·U. Morgner
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Abstract

The polarization states of terahertz (THz) radiation generated in a photo-ionized gas driven by strong two- or multi-frequency fields with locally controlled polarization are studied. We reveal a universal property of the resulting THz waveforms: the ellipticity of their polarization state increases linearly with the frequency. This ``linear chirp of ellipticity'' makes plasma-based THz generation unique among other THz sources. However, it also puts some constraints on the polarization properties of the generated THz radiation. We derive a general expression for the THz ellipticity and demonstrate how the polarization states of the generated THz waveforms can be manipulated and controlled by the polarization of the pump pulses.

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H. Alirezaee, S. Skupin, V. Vaicaitis, A. Demircan, I. Babushkin, Luc Bergé, U. Morgner. 2024-06-06. Universal properties of locally generated terahertz waveforms from polarization-controlled two- and multi-color ionizing fields. https://arxiv.org/abs/2406.03854

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