Image Rotation in Plasmas

Gueroult, Renaud [Universit´e de Toulouse (France)] (ORCID:0000000152089594); Tripathi, Shreekrishna [University of California, Los Angeles, CA (United States)] (ORCID:0000000265002272); Han, Jia [University of California, Los Angeles, CA (United States)] (ORCID:0000000190887757); Pribyl, Patrick [University of California, Los Angeles, CA (United States)]; Rax, Jean-Marcel [Université de Paris-Saclay, Orsay (France)] (ORCID:0000000315124965); Fisch, Nathaniel J. [Princeton University, NJ (United States)] (ORCID:0000000203017380)

doi:10.1103/swrn-w3yf

DOE OSTI · 2589183

Image Rotation in Plasmas

Gueroult, Renaud [Universit´e de Toulouse (France)] (ORCID:0000000152089594)·Tripathi, Shreekrishna [University of California, Los Angeles, CA (United States)] (ORCID:0000000265002272)·Han, Jia [University of California, Los Angeles, CA (United States)] (ORCID:0000000190887757)·Pribyl, Patrick [University of California, Los Angeles, CA (United States)]·Rax, Jean-Marcel [Université de Paris-Saclay, Orsay (France)] (ORCID:0000000315124965)·Fisch, Nathaniel J. [Princeton University, NJ (United States)] (ORCID:0000000203017380)

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Abstract

Because of the speed of light compared to material motion, the dragging of light is difficult to observe under laboratory conditions. Furthermore we report on the first observation of image rotation, i. e. a dragging by the medium of the wave’s transverse structure, of Alfv´en waves in plasmas. Exploiting the naturally slow group velocity of these waves, significant wave rotation is achieved for modest angular frequency. Control over the rotation of the wave’s structure is demonstrated through the plasma rotation imposed by biased electrodes. Remarkably, experimental results are well reproduced by light dragging theory derived for isotropic media, even if magnetized plasmas are anisotropic. In addition to offering new insights into the fundamental issue of angular momentum coupling between waves and media, these findings also open possibilities for new remote rotation sensing tools.

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Alfvén waves Angular momentum of light Light propagation, transmission & absorption Mechanical effects of light on material media Plasma waves

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Gueroult, Renaud [Universit´e de Toulouse (France)] (ORCID:0000000152089594), Tripathi, Shreekrishna [University of California, Los Angeles, CA (United States)] (ORCID:0000000265002272), Han, Jia [University of California, Los Angeles, CA (United States)] (ORCID:0000000190887757), Pribyl, Patrick [University of California, Los Angeles, CA (United States)], Rax, Jean-Marcel [Université de Paris-Saclay, Orsay (France)] (ORCID:0000000315124965), Fisch, Nathaniel J. [Princeton University, NJ (United States)] (ORCID:0000000203017380). 2025-06-17. Image Rotation in Plasmas. https://doi.org/10.1103/swrn-w3yf

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