Recently, radiation pressure acceleration (RPA) has been proposed and extensively studied, which shows that circularly polarized (CP) laser pulses can accelerate mono-energetic ion bunches in a phase-stable-acceleration (PSA) way from ultrathin foils. It is found that self-organizing proton beam can be stably accelerated to GeV in the interaction of a CP laser with a planar target at 1022 W/cm2. A project called Compact LAser Plasma proton Accelerator (CLAPA) is approved by MOST in China recently. A prototype of laser driven proton accelerator (1 to 15 MeV/1 Hz) based on the PSA mechanism and plasma lens is going to be built at Peking University in the next five years. It will be upgraded to 200 MeV later for applications such as cancer therapy, plasma imaging and fast ignition for inertial confine fusion.
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