The development of novel target concepts is crucial to make laser-driven acceleration of ion beams suitable for applications. We tested double-layer targets formed of an ultralow density nanostructured carbon layer ($ensuremath{sim}7ext{ }ext{ }{mathrm{mg}/mathrm{cm}}^{3}$, $8--12ext{ }ext{ }ensuremath{mu}mathrm{m}$--thick) deposited on a $ensuremath{mu}mathrm{m}$--thick solid Al foil. A systematic increase in the total number of the accelerated ions (protons and ${mathrm{C}}^{6+}$) as well as enhancement of both their maximum and average energies was observed with respect to bare solid foil targets. Maximum proton energies up to 30 MeV were recorded. Dedicated three-dimensional particle-in-cell simulations were in remarkable agreement with the experimental results, giving clear indication of the role played by the target nanostructures in the interaction process.
展开▼
