Speaker
Description
Laser–wakefield acceleration (LWFA) [1] is a promising route towards compact high-energy electron accelerators. In this scheme, an intense ultrashort laser pulse propagates through a gas target, driving a plasma wave that can trap and accelerate electrons to relativistic energies over only a few centimeters. LWFA therefore offers a potential path towards compact electron sources for next-generation free-electron lasers (FELs). In this work, we investigate controlled electron injection into the plasma wave using two mechanisms showing promising beam quality in the recent studies: density down-ramp injection [2,3] and truncated ionization injection [4], aiming at high-quality laser-driven acceleration of electron beams at sub-GeV and GeV energies. Using quasi-3D particle-in-cell (PIC) simulations [5,6] together with post-processed interactive visualizations [7], we study the laser–target dynamics and optimization of the longitudinal plasma-density profile, including a density up-ramp in the acceleration region and an optimized exit down-ramp. The goal is to identify experimentally feasible regimes enabling efficient production of high-charge, low-divergence electron beams with favourable energy spread and emittance for FEL realization at the ELI Beamlines Facility [8]. Current work further focuses on adapting the laser and target parameters for initial experiments, supported by combined PIC and computational fluid dynamics (CFD) modelling.
References:
[1] T. Tajima et al., Phys. Rev. Lett. 43, 267–270 (1979)
[2] K. Feng et al., arXiv:2501.09916 (2025)
[3] J. Zhan et al., Phys. Rev. Research 8, 013207 (2026)
[4] S. Maity et al., Phys. Rev. Accel. Beams 29, 093601 (2026)
[5] J. Derouillat et al., Comput. Phys. Commun. 222, 351-373 (2018)
[6] R. A. Fonseca et al., LNCS 2331, 342-351 (2002)
[7] M. Matys et al., Photonics 12, 436 (2025); vbl.eli-beams.eu
[8] A. Molodozhentsev et al., in Proc. IPAC’24, MOPG32 (2024)
Acknowledgements
This work received funding from the European Union’s Horizon Europe research and innovation program, under Grant Agreement No.101079773 (EuPRAXIA Preparatory Phase), No.101188004 (PACRI—Plasma Accelerator systems for Compact Research Infrastructures). Portions of this research were carried out at the ELI Beamlines Facility, a European user facility operated by the Extreme Light Infrastructure ERIC. The computational time was provided by the supercomputers Sunrise of ELI Beamlines facility and Karolina of IT4Innovations - supported by the Ministry of Education, Youth and Sports of the Czech Republic through the e-INFRA CZ (ID:90254).