Enhancement of accelerated proton yield in intense laser irradiating double-layer targets

Accelerated protons in laser-plasma interactions are originated from the hydrocarbon contaminant affiliating on the target surface. A novel scheme of double-layer target is proposed to provide a stable and strong proton source. The Double-layer targets were designed and manufactured by sputtering 200 nm thick Au on 2.5 μm thick Mylar films. The measurement of proton beams in laser-plasma interaction was done by magnetic spectrometer and CR-39 solid state nuclear track detectors. The experimental results suggest that the double-layer target can efficiently increase the yield of protons, and may improve the quality of proton beams.