Mid-Z ion driven fast ignition inertial fusion requires ion beams of hundreds of MeV energy and <10% energy spread. The break-out afterburner (BOA) is one mechanism proposed to generate such beams; however, the late stages of the BOA tend to produce too large of an energy spread. Here we show how use of a second target foil placed behind a nm-scale foil can substantially reduce the temperature of the comoving electrons and improve the ion beam energy spread, leading to ion beams of energy hundreds of MeV and 6% energy spread.
Huang, C. K., Albright, B. J., Yin, L., Wu, H. C., Bowers, K. J., Hegelich, B. M., & Fernández, J. C. (2011). Improving beam spectral and spatial quality by double-foil target in laser ion acceleration. Physical Review Special Topics - Accelerators and Beams, 14(3). https://doi.org/10.1103/PhysRevSTAB.14.031301