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arXiv · 1905.02831

Parallel-Plate Waveguides for Terahertz-Driven MeV Electron Bunch Compression

Mohamed A. K. Othman·Matthias C. Hoffmann·Michael K. Kozina·X. J. Wang·Renkai K. Li·Emilio A. Nanni
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Abstract

We demonstrate the electromagnetic performance of waveguides for femtosecond electron beam bunch manipulation and compression with strong-field terahertz (THz) pulses. The compressor structure is a dispersion-free exponentially-tapered parallel-plate waveguide (PPWG) that can focus single-cycle THz pulses along one dimension. We show test results of the tapered PPWG structure using electro-optic sampling (EOS) at the interaction region with peak fields of at least 300 kV/cm given 0.9 uJ of incoming THz energy. We also present a modified shorted design of the tapered PPWG for better beam manipulation and reduced magnetic field as an alternative to a dual-feed approach. As an example, we demonstrate that with 5 uJ of THz energy, the PPWG compresses a 2.5 MeV electron bunch by a compression factor of more than 4 achieving a bunch length of about 18 fs.

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Mohamed A. K. Othman, Matthias C. Hoffmann, Michael K. Kozina, X. J. Wang, Renkai K. Li, Emilio A. Nanni. 2019-05-07. Parallel-Plate Waveguides for Terahertz-Driven MeV Electron Bunch Compression. https://doi.org/10.1364/oe.27.023791

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