Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Chaotic ratchet dynamics with cold atoms in a pair of pulsed optical
  lattices   We present a very simple model for realizing directed transport with cold
atoms in a pair of periodically flashed optical lattices. The origin of this
ratchet effect is explained and its robustness demonstrated under imperfections
typical of cold atom experiments. We conclude that our model offers a clear-cut
way to implement directed transport in an atom optical experiment.

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The categories of this paper are: eess
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The categories of this paper are: q-fin
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The categories of this paper are: econ
10
The categories of this paper are: q-bio
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The categories of this paper are: bayes-an
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The categories of this paper are: hep-th
0
The categories of this paper are: hep-ph
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The categories of this paper are: cs
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The categories of this paper are: math
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The categories of this paper are: mtrl-th
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The categories of this paper are: alg-geom
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The categories of this paper are: math-ph
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The categories of this paper are: hep-lat
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The categories of this paper are: solv-int
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The categories of this paper are: supr-con
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The categories of this paper are: nucl-th