Laser-driven ion acceleration can provide ultra-short, high-charge,
low-emittance beams. Although undergoing extensive research, demonstrated
maximum energies for laser-ion sources are non-relativistic, complicating
injection into high-β accelerator elements and stopping short of
desirable energies for pivotal applications, such as proton tumor therapy. In
this work, we decouple the efforts towards relativistic beam energies from a
single laser-plasma source via a proof-of-principle concept, boosting the beam
into this regime through only a few plasma stages. We employ full 3D
particle-in-cell simulations to demonstrate the capability for capture of
high-charge beams as produced by laser-driven sources, where both source and
booster stages utilize readily available laser pulse parameters.Comment: 4 pages, 4 figures, submitted for peer revie