Enhanced Proton Acceleration by an Ultrashort Laser with Structured Dynamic Plasma Targets


  E. Schleifer, M. Botton, A. Zigler  
Racah Institute of Physics, The Hebrew University of Jerusalem, Jerusalem 91904, Israel

We experimentally demonstrate a notably enhanced acceleration of protons to high energy by relatively modest ultrashort laser pulses and structured dynamical plasma targets. Realized by special deposition of snow targets on sapphire substrates and using carefully planned prepulses, high proton yields emitted in a narrow solid angle with energy above 21 MeV were detected from a 5 TW laser. Our simulations predict that using the proposed scheme protons can be accelerated to energies above 150 MeV by 100 TW laser systems.