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arXiv · 2103.09817

Observation of mechanical Faraday effect in gas media

Alexander A. Milner·Uri Steinitz·Ilya Sh. Averbukh·Valery Milner
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Abstract

We report the experimental observation of the rotation of the polarization plane of light propagating in a gas of fast-spinning molecules (molecular super-rotors). In the observed effect, related to Fermi's prediction of "polarization drag" by a rotating medium, the vector of linear polarization tilts in the direction of molecular rotation due to the rotation-induced difference in the refractive indices for the left and right circularly polarized components. We use an optical centrifuge to bring the molecules in a gas sample to ultrafast unidirectional rotation and measure the polarization drag angles of the order of 0.2 milliradians in a number of gases under ambient conditions. We demonstrate an all-optical control of the drag magnitude and direction, and investigate the robustness of the mechanical Faraday effect with respect to molecular collisions.

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Alexander A. Milner, Uri Steinitz, Ilya Sh. Averbukh, Valery Milner. 2021-03-16. Observation of mechanical Faraday effect in gas media. https://doi.org/10.1103/physrevlett.127.073901

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