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arXiv · 1109.1521

Focusing of Intense Subpicosecond Laser Pulses in Wedge Targets

M. C. Levy·A. J. Kemp·S. C. Wilks·L. Divol·M. G. Baring
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Abstract

Two dimensional particle-in-cell simulations characterizing the interaction of ultraintense short pulse lasers in the range 10^{18} \leq I \leq 10^{20} W/cm^{2} 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 10^{20} W/cm^{2} at 1 μm wavelength.

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M. C. Levy, A. J. Kemp, S. C. Wilks, L. Divol, M. G. Baring. 2011-09-07. Focusing of Intense Subpicosecond Laser Pulses in Wedge Targets. https://doi.org/10.1063/1.3646309

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