Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Magnetic Field Enhanced Coherence Length in Cold Atomic Gases   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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The categories of this paper are: math-ph
9
The categories of this paper are: nlin
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The categories of this paper are: quant-ph
0
The categories of this paper are: hep-ph
16
The categories of this paper are: stat
23
The categories of this paper are: solv-int
8
The categories of this paper are: hep-ex
12
The categories of this paper are: nucl-th
33
The categories of this paper are: plasm-ph
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The categories of this paper are: q-alg
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The categories of this paper are: q-bio
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The categories of this paper are: astro-ph
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The categories of this paper are: math
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The categories of this paper are: comp-gas
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The categories of this paper are: q-fin
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The categories of this paper are: bayes-an