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arXiv · 2601.00134

Generation and characterization of coherent terahertz radiation from 100-TW laser-wakefield acceleration

Taegyu Pak·Dae Hee Wi·Sang Beom Kim·Jaewon Lim·Jae Hee Sung·Seong Ku Lee·Ki-Yong Kim
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Abstract

We experimentally characterized terahertz (THz) radiation emitted from laser-wakefield acceleration (LWFA) driven at 100-TW laser power. Simultaneous measurements of the laser energy, electron-bunch charge, and THz energy reveal a quadratic dependence of the THz energy on both charge and laser energy. This behavior indicates coherent collective emission in the generation process and provides a useful scaling law for THz output. Microbolometer-based beam profiling shows a relatively large THz beam divergence (~0.2 rad). Single-shot THz interferometry further shows that the emitted THz pulse is sub-picosecond in duration and broadband. Combining the beam-profile and interferometric measurements, the THz spectrum is expected to span approximately 1-20 THz. Together, these results support coherent acceleration radiation as the dominant mechanism for THz generation in 100-TW LWFA.

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Taegyu Pak, Dae Hee Wi, Sang Beom Kim, Jaewon Lim, Jae Hee Sung, Seong Ku Lee, Ki-Yong Kim. 2025-12-31. Generation and characterization of coherent terahertz radiation from 100-TW laser-wakefield acceleration. https://arxiv.org/abs/2601.00134

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