Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Decay of Quantum Correlations in Atom Optics Billiards with Chaotic and
  Mixed Dynamics   We perform echo spectroscopy on ultra cold atoms in atom optics billiards, to
study their quantum dynamics. The detuning of the trapping laser is used to
change the ``perturbation'', which causes a decay in the echo coherence. Two
different regimes are observed: First, a perturbative regime in which the decay
of echo coherence is non-monotonic and partial revivals of coherence are
observed. These revivals are more pronounced in traps with mixed dynamics as
compared to traps where the dynamics is fully chaotic. Next, for stronger
perturbations, the decay becomes monotonic and independent of the strength of
the perturbation. In this regime no clear distinction can be made between
chaotic traps and traps with mixed dynamics.

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The categories of this paper are: eess
5
The categories of this paper are: gr-qc
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The categories of this paper are: math-ph
1
The categories of this paper are: cs
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The categories of this paper are: astro-ph
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The categories of this paper are: dg-ga
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The categories of this paper are: ao-sci
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The categories of this paper are: plasm-ph
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The categories of this paper are: q-fin
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The categories of this paper are: hep-ex
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The categories of this paper are: bayes-an
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The categories of this paper are: cond-mat
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The categories of this paper are: q-alg
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The categories of this paper are: mtrl-th
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The categories of this paper are: comp-gas
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The categories of this paper are: patt-sol