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arXiv · 2505.12475

Multi-Dimensional Phase Space Manipulation for Attosecond Electron Bunch Compression

Yuxin Cheng·Chao Feng·Qiang Gu
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Abstract

Attosecond electron beams are essential for investigating ultrafast structural and electronic dynamics in matter with atomic-scale resolution. We propose a novel method that enables robust attosecond-level electron bunch compression. This method employs THz-driven linear energy chirping and multidimensional phase-space manipulation, effectively compressing the electron bunch and suppressing its arrival timing jitter. Implemented in an MeV ultrafast electron diffraction beamline, this method compresses a 3~MeV, 0.1~pC electron beam from an initial duration of 50~fs to 810~as while retaining 6~fC of charge, with 850~as arrival-time jitter. This approach enables unprecedented timing resolution in ultrafast sciences and offers significant potential for other accelerator applications involving attosecond-scale electron beams.

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Yuxin Cheng, Chao Feng, Qiang Gu. 2025-05-18. Multi-Dimensional Phase Space Manipulation for Attosecond Electron Bunch Compression. https://arxiv.org/abs/2505.12475

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