Laser-Triggered Proton Acceleration From Micro-Structured thin Targets

By using relativistic massively parallel PIC code MANDOR, which features arbitrary target design including 3D micro-structuring, a study of ion acceleration in short laser pulse interaction with different thin targets has been performed. Based on 3D simulation results it has been shown that micro-structures on the front surface of thin plane targets increase a number and energy of hot electrons in comparison with that for the case of pure plain foils of optimal thickness. As a result, the energy of accelerated ions also increases up to 50%. However, the efficiency of ion acceleration from structured target reduces with laser pulse intensity increase, so that for laser pulses of ultra-relativistic intensity a positive role of surface micro-structuring diminishes. We have also studied to which extent a sub-ps imperfection of the laser pulse shape, which smoothes the surface micro-structures suppresses high-energy ion generation. ((c) 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)