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arXiv · 2206.13572

Electro-optic sampling based characterization of broad-band high efficiency THz-FEL

Maximilian Lenz·Andrew Fisher·Youna Park·Alexander Ody·Pietro Musumeci
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Abstract

Extremely high beam-to-radiation energy conversion efficiencies can be obtained in a THz FEL using a strongly tapered helical undulator at the zero-slippage resonant condition, where a circular waveguide is used to match the radiation group velocity to the electron beam longitudinal velocity. In this paper we report on the first electro-optic sampling (EOS) based measurements of the broadband THz FEL radiation pulses emitted in this regime. The THz field waveforms are reconstructed in the spatial and temporal domains using multi-shot and single-shot EOS schemes respectively. The measurements are performed varying the input electron beam energy in the undulator providing insights on the complex dynamics in a waveguide FEL.

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Maximilian Lenz, Andrew Fisher, Youna Park, Alexander Ody, Pietro Musumeci. 2022-06-27. Electro-optic sampling based characterization of broad-band high efficiency THz-FEL. https://doi.org/10.1364/oe.467677

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