Two-dimensional particle-in-cell simulation of energetic proton generation by an intense ultrashort laser pulse

摘要

Two-dimensional particle-in-cell (PIC) simulations of fast particles produced by a short laser pulse with a duration of 40 fs and all intensity of 10(20) W cm(-2) interacting with a foil target are performed. The dependence of the energy of the generated fast protons on the target geometry is examined. The absorbed laser energy is transferred to fast electrons, which interact with the foil and are partially ejected from the foil surfaces. These electrons produce an electric field that causes a proton beam to be emitted from the rear surface of the foil. Various kinds of target are considered. The optimum target plasma conditions for the maximum proton acceleration are determined.