Laser-driven ion acceleration from ultra-thin foil targets: Role of plasma structures

Recent progress in high power laser technology enables laser intensities up to 1021 W/cm2 to be achieved. Such lasers are now available in a number of laboratories worldwide, including the PHELIX facility at GSI. Typical pulses have durations from tens to hundreds of femtoseconds and carry electric fields in the order of TV/m. They ionise solid targets and form laser-plasma of highly relativistic electrons. The radiation pressure of the focused laser light separates electrons from ions creating TV/m electrostatic fields, accelerating ions to multi-tens of MeV/nucleon. In this talk, I will present recent experiment and simulation results from our group on ion acceleration from ultra-thin (tens of nanometre) foils. I will focus on results from foils undergoing relativistic induced transparency and discuss how laser-generated plasma structures, produced by the collective response of the plasma electrons to the propagating laser pulse, affects ion acceleration and can be used to control the ion beam energy and spatial profile.