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arXiv · 2604.16059

Controlling external injection in laser-plasma accelerators with terahertz frequency bunch manipulation

Aras Amini·Lewis R. Reid·James K. Jones·Morgan T. Hibberd·Laura Corner·Darren M. Graham·Steven P. Jamison·Graeme Burt·Robert B. Appleby
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Abstract

Laser-plasma wakefield acceleration (LWFA) offers ultrahigh accelerating gradients in compact setups, but the complex non-linear nature of the process makes it challenging to generate high-quality beams. Injection of electron bunches from an external source into a plasma accelerator provides a promising route to improved performance; however, electron bunches from conventional radio-frequency (RF)-based injectors suffer from non-linear compression and laser-beam asynchrony, leading to energy jitter and emittance growth. We present a fundamental concept of terahertz-controlled electron bunches for external injection into LWFA. This terahertz-frequency approach provides temporal locking between the electron beam and the drive laser, and enables the compression of high-quality beams to sub-10-fs durations before injection into the LWFA. Numerical simulations demonstrate that GeV-scale acceleration with excellent beam quality and stability -- energy jitter and energy spread around 0.2% -- can be achieved using this method. This concept opens new opportunities for stable, multi-stage laser-driven accelerators and supports the development of next-generation applications such as free-electron lasers (FELs).

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Aras Amini, Lewis R. Reid, James K. Jones, Morgan T. Hibberd, Laura Corner, Darren M. Graham, Steven P. Jamison, Graeme Burt, Robert B. Appleby. 2026-04-17. Controlling external injection in laser-plasma accelerators with terahertz frequency bunch manipulation. https://arxiv.org/abs/2604.16059

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