Focusing of intense subpicosecond laser pulses in wedge targets

Abstract

Two dimensional particle-in-cell simulations characterizing the interaction of ultraintense short pulse lasers in the range 1018 ≤ I ≤ 1020 Wcm2 with converging target geometries are presented. Seeking to examine intensity amplification in high-power laser systems, where focal spots are typically non-diffraction limited, we describe key dynamical features as the injected laser intensity and convergence angle of the target are systematically varied. We find that laser pulses are focused down to a wavelength with the peak intensity amplified by an order of magnitude beyond its vacuum value and develop a simple model for how the peak location moves back towards the injection plane over time. This performance is sustained over hundreds of femtoseconds and scales to laser intensities beyond 1020 Wcm2 at 1 m wavelength. © 2011 American Institute of Physics.