Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Gap soliton dynamics in an optical lattice as a parametrically driven
  pendulum   A long wavelength optical lattice is generated in a two-level medium by
low-frequency contrapropagating beams. Then a short wave length gap soliton
generated by evanescent boundary instability (supratransmission) undergoes a
dynamics shown to obey the Newton equation of the parametrically driven
pendulum, hence presenting extremely rich, possibly chaotic, dynamical
behavior. The theory is sustained by numerical simulations and provides an
efficient tool to study soliton trajectories.

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The categories of this paper are: cmp-lg
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The categories of this paper are: q-bio
1
The categories of this paper are: cs
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The categories of this paper are: ao-sci
2
The categories of this paper are: math
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The categories of this paper are: atom-ph
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The categories of this paper are: nucl-th
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The categories of this paper are: hep-th
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The categories of this paper are: eess
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The categories of this paper are: funct-an
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The categories of this paper are: hep-ex
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The categories of this paper are: q-fin
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The categories of this paper are: dg-ga
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The categories of this paper are: adap-org
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The categories of this paper are: chao-dyn
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The categories of this paper are: supr-con