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arXiv · 1812.09429

Laser Amplification in Strongly-Magnetized Plasma

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

We consider backscattering of laser pulses in strongly-magnetized plasma mediated by kinetic magnetohydrodynamic waves. Magnetized low-frequency scattering, which can occur when the external magnetic field is neither perpendicular nor parallel to the laser propagation direction, provides an instability growth rate higher than Raman scattering and a frequency downshift comparable to Brillouin scattering. In addition to the high growth rate, which allows smaller plasmas, and the 0.1-2\% frequency downshift, which permits a wide range of pump sources, MLF scattering is an ideal candidate for amplification because the process supports an extremely large bandwidth, which particle-in-cell simulations show produces ultrashort durations. Under some conditions, MLF scattering also becomes the dominant spontaneous backscatter instability, with implications for magnetized laser-confinement experiments.

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Matthew R. Edwards, Yuan Shi, Julia M. Mikhailova, Nathaniel J. Fisch. 2018-12-22. Laser Amplification in Strongly-Magnetized Plasma. https://doi.org/10.1103/physrevlett.123.025001

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