A double-foil target for improving beam quality in laser ion acceleration with thin foils

摘要

A double-foil target is proposed for laser ion acceleration with thin targets to take advantage of high efficiency of such targets while avoiding beam degradation in late stage of acceleration. Laser heating of electrons co-moving with the ion beam is stopped by the second foil. It is found that the second foil can also modify and substantially improve the spectral and spatial properties of the ion beam and reduce the temperature of the co-moving electrons, leading to better preservation of the beam quality. Details of the dynamics are studied with particle-in-cell simulations.