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arXiv · 2007.13286

Flowing cryogenic liquid target for terahertz wave generation

Yiwen E·Yuqi Cao·Fang Ling·X. -C. Zhang
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Abstract

Terahertz wave emission from condensed matter excited by intense laser pulses not only reflects the details in laser-matter interaction but also offers bright terahertz wave sources. Flowing liquid targets possess the advantage of providing a fresh area for each laser pulse. To demonstrate a debris-free target under laser excitation, we investigate the use of liquid nitrogen as a target. By creating a flowing liquid nitrogen line in the ambient environment, we successfully observe broadband terahertz wave emission under short pulse excitation. Our cryogenic line is able to sustain the excitation of a high-repetition-rate (1 kHz) laser. The terahertz peak field emitted from liquid nitrogen is comparable to that from liquid water, yet a broader bandwidth is observed. This demonstration prompts new opportunities in choosing potential materials for studying terahertz wave generation process and in understanding laser-induced ionization in different liquids.

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Yiwen E, Yuqi Cao, Fang Ling, X. -C. Zhang. 2020-07-27. Flowing cryogenic liquid target for terahertz wave generation. https://doi.org/10.1063/5.0023106

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