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arXiv · 1902.07510

High-efficiency broadband THz emission via diffraction-radiation cavity

Yosuke Honda·Miho Shimada·Alexander Aryshev·Ryukou Kato·Tsukasa Miyajima·Takashi Obina·Ryota Takai·Takashi Uchiyama·Naoto Yamamoto
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Abstract

Accelerator-based terahertz (THz) radiation has been expected to realize a high-power broadband source. Employing a low-emittance and short-bunch electron beam at a high repetition rate, a scheme of coherent diffraction-radiation in an optical cavity layout is proposed. The scheme's stimulated radiation process between bunches can greatly enhance the efficiency of the radiation emission. We performed an experiment with a superconducting linac constructed as an energy recovery linac (ERL) test facility. The electron beam passes through small holes in the cavity mirrors without being destroyed. A sharp THz resonance signal, which indicates broadband stimulated radiation correlated with beam deceleration, was observed while scanning the round-trip length of the cavity. This observation proves the efficient beam-to-radiation energy conversion due to the stimulated radiation process.

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Yosuke Honda, Miho Shimada, Alexander Aryshev, Ryukou Kato, Tsukasa Miyajima, Takashi Obina, Ryota Takai, Takashi Uchiyama, Naoto Yamamoto. 2019-02-20. High-efficiency broadband THz emission via diffraction-radiation cavity. https://doi.org/10.1103/physrevaccelbeams.22.040703

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