Generation of focusing ion beams by magnetized electron sheath acceleration

• Published in: Scientific reports Vol. 10; no. 1; p. 18966
• Main Authors: Weichman, K., Santos, J. J., Fujioka, S., Toncian, T., Arefiev, A. V.
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 03.11.2020; Nature Publishing Group
• Subjects: 639/766; 639/766/1960/1135; CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ENGINEERING; Humanities and Social Sciences; Magnetic fields; Magnetism; multidisciplinary; Science; Science (multidisciplinary)
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-020-75915-8

We present the first 3D fully kinetic simulations of laser driven sheath-based ion acceleration with a kilotesla-level applied magnetic field. The application of a strong magnetic field significantly and beneficially alters sheath based ion acceleration and creates two distinct stages in the acceleration process associated with the time-evolving magnetization of the hot electron sheath. The first stage delivers dramatically enhanced acceleration, and the second reverses the typical outward-directed topology of the sheath electric field into a focusing configuration. The net result is a focusing, magnetic field-directed ion source of multiple species with strongly enhanced energy and number. The predicted improvements in ion source characteristics are desirable for applications and suggest a route to experimentally confirm magnetization-related effects in the high energy density regime. We additionally perform a comparison between 2D and 3D simulation geometry, on which basis we predict the feasibility of observing magnetic field effects under experimentally relevant conditions.