Dynamics of nanosecond laser pulse propagation and of associated instabilities in a magnetized underdense plasma

W. Yao; A. Higginson; J. -R. Marquès; P. Antici; J. Béard; K. Burdonov; M. Borghesi; A. Castan; A. Ciardi; B. Coleman; S. N. Chen; E. d'Humières; T. Gangolf; L. Gremillet; B. Khiar; L. Lancia; P. Loiseau; X. Ribeyre; A. Soloviev; M. Starodubtsev; Q. Wang; J. Fuchs

doi:10.1103/physrevlett.130.265101

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arXiv · 2211.06036

Dynamics of nanosecond laser pulse propagation and of associated instabilities in a magnetized underdense plasma

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Abstract

The propagation and energy coupling of intense laser beams in plasmas are critical issues in laser-driven inertial confinement fusion. Applying magnetic fields to such a setup has been evoked to enhance fuel confinement and heating, and mitigate laser energy losses. Here we report on experimental measurements demonstrating improved transmission and increased smoothing of a high-power laser beam propagating in an underdense magnetized plasma. We also measure enhanced backscattering, which our simulations show is due to hot electrons confinement, thus leading to reduced target preheating.

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W. Yao, A. Higginson, J. -R. Marquès, P. Antici, J. Béard, K. Burdonov, M. Borghesi, A. Castan, A. Ciardi, B. Coleman, S. N. Chen, E. d'Humières, T. Gangolf, L. Gremillet, B. Khiar, L. Lancia, P. Loiseau, X. Ribeyre, A. Soloviev, M. Starodubtsev, Q. Wang, J. Fuchs. 2022-11-11. Dynamics of nanosecond laser pulse propagation and of associated instabilities in a magnetized underdense plasma. https://doi.org/10.1103/physrevlett.130.265101

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