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arXiv · 2602.12765

Demonstration of ultra-low emittance beams in a kHz laser wakefield accelerator and application to electron diffraction

J. Monzac·S. Smartsev·J. Huijts·A. Vernier·I. A. Andriyash·V. Tomkus·V. Girdauskas·G. Raciukaitis·M. Mackeviciute·V. Stankevic·A. Cavagna·J. Kaur·A. Kalouguine·R. Lopez-Martens·J. Faure
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Abstract

We present a compact, cost-effective method for measuring the emittance of kHz-repetition-rate laser-wakefield accelerated electron beams using a permanent solenoid. The measured normalized emittance, $\epsilon_n = 124\,\mathrm{nm \cdot rad}$ ($\simeq 0.04 \pi\,\mathrm{mm \cdot mrad}$) at $2.7\,$MeV, is comparable to that of ultra-low emittance radiofrequency guns used for electron diffraction. Leveraging this low emittance, we successfully applied the electron beam to electron diffraction. We demonstrate diffraction images obtained from a single-crystal silicon nanomembrane sample, clearly resolving diffraction peaks across multiple orders.

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J. Monzac, S. Smartsev, J. Huijts, A. Vernier, I. A. Andriyash, V. Tomkus, V. Girdauskas, G. Raciukaitis, M. Mackeviciute, V. Stankevic, A. Cavagna, J. Kaur, A. Kalouguine, R. Lopez-Martens, J. Faure. 2026-02-13. Demonstration of ultra-low emittance beams in a kHz laser wakefield accelerator and application to electron diffraction. https://arxiv.org/abs/2602.12765

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