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Magnetic Field Enhanced Coherence Length in Cold Atomic Gases

Olivier Sigwarth·Guillaume Labeyrie·Thibaut Jonckheere·Dominique Delande·Robin Kaiser·Christian Miniatura
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Abstract

We study the effect of an external magnetic field on coherent backscattering of light from a cool rubidium vapor. We observe that the backscattering enhancement factor can be {\it increased} with $B$. This surprising behavior shows that the coherence length of the system can be increased by applying a magnetic field, in sharp contrast with ususal situations. This is mainly due to the lifting of the degeneracy between Zeeman sublevels. We find good agreement between our experimental data and a full Monte-Carlosimulation, taking into account the magneto-optical effects and the geometry of the atomic cloud.

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Olivier Sigwarth, Guillaume Labeyrie, Thibaut Jonckheere, Dominique Delande, Robin Kaiser, Christian Miniatura. 2005-06-30. Magnetic Field Enhanced Coherence Length in Cold Atomic Gases. https://doi.org/10.1103/physrevlett.93.143906

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