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arXiv · 2509.23294

Programmable Focal Elongation and Shaping of High-Intensity Laser Pulses using Adaptive Optics

P. Blum·A. Puchert·E. Archer·S. Jalas·S. W. Jolly·J. Osterhoff·W. P. Leemans·M. Kirchen·A. R. Maier·R. J. Shalloo
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Abstract

Controlling the intensity distribution of laser pulses in the focal region is essential for optimizing optically generated plasma waveguides and enabling advanced plasma acceleration techniques, including dephasingless wakefield acceleration. Here, we present a method for programmatic structuring of the high-intensity focal region of a standard off-axis parabolic mirror, extending the length of this region well beyond the Rayleigh length and enabling control over the longitudinal intensity distribution. The theoretical framework is validated through numerical simulations and experimental measurements. Further, we demonstrate the use of this technique in an existing plasma accelerator system using readily available hardware components. Finally, we illustrate the potential application of this method to multi-GeV laser plasma acceleration and the generation of flying foci, research areas which would significantly benefit from improved programmatic structuring of high-intensity laser pulses.

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P. Blum, A. Puchert, E. Archer, S. Jalas, S. W. Jolly, J. Osterhoff, W. P. Leemans, M. Kirchen, A. R. Maier, R. J. Shalloo. 2025-09-27. Programmable Focal Elongation and Shaping of High-Intensity Laser Pulses using Adaptive Optics. https://doi.org/10.1364/ol.579664

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