Characterization of thin films for TNSA laser irradiation

Thin films of hydrogenated materials have been prepared, at Messina University, to be irradiated by high intensity lasers in TNSA conditions in order to accelerate high energetic protons with high yield and directivity. Film composition was based on polymers, metals, multilayers and nanostructures embedded in polymers. The preparation methods were different and based on different deposition techniques. High vacuum condition, nanostructures, carbon nanotubes, metal oxides and hydrates, were employed. Targets were prepared as a sheath with thicknesses ranging between 0.1 and 100 μm and surfaces of the order of some cm2. Targets were characterized in terms of thickness, roughness, surface morphology, colours and absorption coefficient in the wavelength range 250 nm-1300 nm. Peculiar attention is given to samples with high absorption coefficient in order to improve the energy transfer from the coherent light to the generated plasma. © Published under licence by IOP Publishing Ltd