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arXiv · 2111.13243

Kilo-Tesla axial magnetic field generation with high intensity spin and orbital angular momentum beams

Andrew Longman·Robert Fedosejevs
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Abstract

Absorption of angular momentum from a high intensity laser pulse can lead to the generation of strong axial magnetic fields in plasma. The effect, known as the inverse Faraday effect can generate kilo-Tesla strength, multi-picosecond, axial magnetic fields extending over hundreds of microns in underdense plasma. In this paper we explore the effect with ultra-high intensity circularly polarized Gaussian beams and linearly polarized orbital angular momentum beams comparing analytic expressions with 3D particle-in-cell simulations. We develop a model for the transverse magnetic field profiles, introduce a new model for the temporal decay, and show that while the magnetic field strength is independent of plasma density, it has a strong dependence on the laser beam waist.

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Andrew Longman, Robert Fedosejevs. 2021-11-25. Kilo-Tesla axial magnetic field generation with high intensity spin and orbital angular momentum beams. https://arxiv.org/abs/2111.13243

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