Abstract
A new scheme for a laser-driven proton accelerator based on a sharply tailored near-critical-density plasma target is proposed. The designed plasma profile allows for the laser channeling of the dense plasma, which triggers a two-stage acceleration of protons—first accelerated by the laser acting as a snowplow in plasma, and then by the collisionless shock launched from the sharp density downramp. Thanks to laser channeling in the near-critical plasma, the formed shock is radially small and collimated. This allows it to generate a significant space-charge field, which acts as a monochromator, defocusing the lower energy protons while the highest ones remain collimated. Our theoretical and numerical analysis demonstrates production of high-energy proton beams with few tens of percent energy spread, few degrees divergence angle and charge up to few nC. With a PW-class ultrashort laser this scheme predicts the generation of such high quality proton beams with energies up to several hundreds of MeV.
- Received 2 October 2018
DOI:https://doi.org/10.1103/PhysRevAccelBeams.22.021301
Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI.
Published by the American Physical Society