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arXiv · 2212.13404

Generation of ultrabrilliant polarized attosecond electron bunch via dual-wake injection

Ting Sun·Qian Zhao·Feng Wan·Yousef I. Salamin·Jian-Xing Li
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Abstract

Laser wakefield acceleration is paving the way for the next generation of electron accelerators, for their own sake and as radiation sources. A controllable dual-wake injection scheme is put forward here to generate an ultrashort triplet electron bunch with high brightness and high polarization, employing a radially polarized laser as a driver. We find that the dual wakes can be driven by both transverse and longitudinal components of the laser field in the quasi-blowout regime, sustaining the laser-modulated wakefield which facilitates the sub-cycle and transversely-split injection of the triplet bunch. {Polarization of the triplet bunch can be highly preserved due to the laser-assisted collective spin precession and the non-canceled transverse spins. In our three-dimensional particle-in-cell simulations, the triplet electron bunch, with duration about $500$ as, six-dimensional brightness exceeding $10^{14}$ A/m$^2$/0.1$\%$ and polarization over $80\%$, can be generated using a few-terawatt laser}. Such an electron bunch could play an essential role in many applications, such as ultrafast imaging, nuclear structure and high-energy physics studies, and the operation of coherent radiation sources.

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Ting Sun, Qian Zhao, Feng Wan, Yousef I. Salamin, Jian-Xing Li. 2022-12-27. Generation of ultrabrilliant polarized attosecond electron bunch via dual-wake injection. https://arxiv.org/abs/2212.13404

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