Plasma Lenses for Relativistic Laser Beams in Laser Wakefield Accelerators

Ming Zeng; Alberto Martinez de la Ossa; Kristjan Poder; Jens Osterhoff

doi:10.1063/1.5116416

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arXiv · 1901.07974

Plasma Lenses for Relativistic Laser Beams in Laser Wakefield Accelerators

Ming Zeng·Alberto Martinez de la Ossa·Kristjan Poder·Jens Osterhoff

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Abstract

Focusing petawatt-level laser beams to a variety of spot sizes for different applications is expensive in cost, labor and space. In this paper, we propose a plasma lens to flexibly resize the laser beam by utilizing the laser self-focusing effect. Using a fixed conventional focusing system to focus the laser a short distance in front of the plasma, we can adjust the effective laser beam waist within a certain range, as if a variety of focusing systems were used with the plasma lens acting as an adjustable eyepiece in a telescope. Such a setup is a powerful tool for laser wakefield accelerator experiments in state-of-art petawatt laser projects and allows for scanning focal spot parameters.

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Ming Zeng, Alberto Martinez de la Ossa, Kristjan Poder, Jens Osterhoff. 2019-01-23. Plasma Lenses for Relativistic Laser Beams in Laser Wakefield Accelerators. https://doi.org/10.1063/1.5116416

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