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arXiv · 1512.00744

Strongly Enhanced Stimulated Brillouin Backscattering in an Electron-Positron Plasma

Matthew R. Edwards·Nathaniel J. Fisch·Julia M. Mikhailova
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Abstract

Stimulated Brillouin backscattering of light is shown to be drastically enhanced in electron-positron plasmas, in contrast to the suppression of stimulated Raman scattering. A generalized theory of three-wave coupling between electromagnetic and plasma waves in two-species plasmas with arbitrary mass ratios, confirmed with a comprehensive set of particle-in-cell simulations, reveals violations of commonly-held assumptions about the behavior of electron-positron plasmas. Specifically, in the electron-positron limit three-wave parametric interaction between light and the plasma acoustic wave can occur, and the acoustic wave phase velocity differs from its usually assumed value.

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Matthew R. Edwards, Nathaniel J. Fisch, Julia M. Mikhailova. 2016-01-07. Strongly Enhanced Stimulated Brillouin Backscattering in an Electron-Positron Plasma. https://doi.org/10.1103/physrevlett.116.015004

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