Near-100 MeV protons via a laser-driven transparency-enhanced hybrid acceleration scheme

Higginson, A. and Gray, R. J. and King, M. and Dance, R. J. and Williamson, S. D. R. and Butler, N. M. H. and Wilson, R. and Capdessus, R. and Armstrong, C. and Green, J. S. and Hawkes, S. J. and Martin, P. and Wei, W. Q. and Mirfayzi, S. R. and Yuan, X. H. and Kar, S. and Borghesi, M. and Clarke, R. J. and Neely, D. and McKenna, P. (2018) Near-100 MeV protons via a laser-driven transparency-enhanced hybrid acceleration scheme. Nature Communications, 9. 724. ISSN 2041-1723

[img]
Preview
Text (Higginson-etal-NC-2018-Near-100-MeV-protons-via-a-laser-driven-transparency-enhanced-hybrid-acceleration-scheme)
Higginson_etal_NC_2018_Near_100_MeV_protons_via_a_laser_driven_transparency_enhanced_hybrid_acceleration_scheme.pdf
Final Published Version
License: Creative Commons Attribution 4.0 logo

Download (1MB)| Preview

    Abstract

    The range of potential applications of compact laser-plasma ion sources motivates the development of new acceleration schemes to increase achievable ion energies and conversion efficiencies. Whilst the evolving nature of laser-plasma interactions can limit the effectiveness of individual acceleration mechanisms, it can also enable the development of hybrid schemes, allowing additional degrees of control on the properties of the resulting ion beam. Here we report on an experimental demonstration of efficient proton acceleration to energies exceeding 94 MeV via a hybrid scheme of radiation pressure-sheath acceleration in an ultrathin foil irradiated by a linearly polarized laser pulse. This occurs via a double-peaked electrostatic field structure, which, at an optimum foil thickness, is significantly enhanced by relativistic transparency and an associated jet of superthermal electrons. The range of parameters over which this hybrid scenario occurs is discussed and implications for ion acceleration driven by next generation, multi-petawatt laser facilities are explored.