Speaker
Ms
Arianna Formenti
(Politecnico di Milano)
Description
Laser-plasma ion sources have been experimentally and theoretically investigated for a long time now. Major improvements in the acceleration process, i.e. increase of ion maximum energy and total charge, can be obtained using advanced targets, without raising laser requirements.
In our contribution we present recent experimental and numerical results of laser-driven ion acceleration with an advanced, robust targetry concept: foam-based multilayer targets. They consist in solid thin foils coated with a porous nanostructured Carbon layer at near-critical density for typical Ti:Sapphire laser systems. In this condition the foam density and the laser frequency match each other so that a complex interaction takes place, enhancing the acceleration process.
Experimental campaigns over wide ranges of laser and target parameters show that the foam may allow for a systematic increase of proton cutoff energy and number, allowing to obtain tens of MeVs protons with few Joules lasers.
Numerical simulations suggest that such improvement is a consequence of a higher conversion efficiency of laser energy into electron kinetic energy, with respect to bare targets. They also show that several features of the interaction physics, e.g. energy absorption, depend on the sub-micrometer structure of the target material.
Primary author
Ms
Arianna Formenti
(Politecnico di Milano)
