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arXiv:2508.11480 · New Journal of Physics

Anisotropic fluorescence signals retarded dipole-dipole interactions in a thermal atomic cloud

Vyacheslav Shatokhin, Friedemann Landmesser, Mario Niebuhr, Frank Stienkemeier, Andreas Buchleitner, Lukas Bruder

Published May 11, 2026• 2 citations
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Abstract

Abstract We experimentally observe and theoretically explain anisotropic multiple quantum coherence signals in the fluorescence from dilute thermal potassium vapours, at room temperature and particle densities ∼ 10 8 cm − 3 . We identify the retarded part of the geometrically fully resolved inter-atomic, resonant dipole-dipole interaction as the crucial ingredient to theoretically reproduce all qualitative features of the experimental spectra.

DOI
10.1088/1367-2630/ae6bae

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