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arXiv · 1903.08955

Kinetic plasma waves carrying orbital angular momentum

D. Blackman·R. Nuter·Ph. Korneev·V. T. Tikhonchuk
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Abstract

The structure of Langmuir plasma waves carrying a finite angular orbital momentum is revised in the paraxial optics approximation. It is shown that the kinetic effects related to higher-order momenta of the electron distribution function lead to coupling of Laguerre-Gaussian modes and result in modification of the wave dispersion and damping. The theoretical analysis is compared to the three-dimensional particle-in-cell numerical simulations for a mode with orbital momentum l = 2. It is demonstrated that propagation of such a plasma wave is accompanied with generation of quasi-static axial and azimuthal magnetic fields which are consequence of the longitudinal and orbital momentum transported with the wave.

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D. Blackman, R. Nuter, Ph. Korneev, V. T. Tikhonchuk. 2019-03-21. Kinetic plasma waves carrying orbital angular momentum. https://doi.org/10.1103/physreve.100.013204

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