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arXiv · 2011.02233

Enhanced Tuneable Rotatory Power in a Rotating Plasma

R. Gueroult·J. -M. Rax·N. J. Fisch
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Abstract

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, for the first time, 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 non-reciprocal elements. The very large rotation frequency of a dense non-neutral plasma could enable unprecedented gyrotropy in the THz regime.

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R. Gueroult, J. -M. Rax, N. J. Fisch. 2020-11-04. Enhanced Tuneable Rotatory Power in a Rotating Plasma. https://doi.org/10.1103/physreve.102.051202

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