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DOE OSTI · 1850399

Enhanced tuneable rotatory power in a rotating plasma

Gueroult, Renaud·Rax, Jean-Marcel·Fisch, Nathaniel J.
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Abstract

We report that the gyrotropic properties of a rotating magnetized plasma are derived analytically. Mechanical rotation leads to a new cutoff for wave propagation along the magnetic field, and polarization rotation above this cutoff is the sum of the classical magneto-optical Faraday effect and the mechanico-optical polarization drag. Exploiting the very large effective group index near the cutoff, we expose here that polarization drag can be 10 4 larger than Faraday rotation at GHz frequency. The rotation leads to weak absorption while allowing direct frequency control, demonstrating the unique potential of rotating plasmas for nonreciprocal elements. The very large rotation frequency of a dense non-neutral plasma could enable unprecedented gyrotropy in the THz regime.

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICSFaraday effectbirefringenceelectromagnetic waveshigh-energy-density plasmasmagneto-optical effectoscillationspolarization of light

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Gueroult, Renaud, Rax, Jean-Marcel, Fisch, Nathaniel J.. 2020-11-19. Enhanced tuneable rotatory power in a rotating plasma. https://doi.org/10.1103/physreve.102.051202

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