Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Nonlinear order parameter oscillations and lattice coupling in
  strongly-driven charge-density-wave systems   The anharmonic response of charge-density wave (CDW) order to strong
laser-pulse perturbations in 1T-TaS_2 and TbTe_3 is investigated by means of a
multiple-pump-pulse time-resolved femtosecond optical spectroscopy. We observe
remarkable anharmonic effects hitherto undetected in the systems exhibiting
collective charge ordering. The efficiency for additional excitation of the
amplitude mode by a laser pulse becomes periodically modulated after the mode
is strongly excited into a coherently oscillating state. A similar effect is
observed also for some other phonons, where the cross-modulation at the
amplitude-mode frequency indicates anharmonic interaction of those phonons with
the amplitude mode. By analyzing the observed phenomena in the framework of
time-dependent Ginzburg-Landau theory we attribute the effects to the
anharmonicity of the mode potentials inherent to the broken symmetry state of
the CDW systems.

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The categories of this paper are: q-alg
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The categories of this paper are: bayes-an
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The categories of this paper are: adap-org
19
The categories of this paper are: eess
5
The categories of this paper are: gr-qc
29
The categories of this paper are: funct-an
33
The categories of this paper are: plasm-ph
8
The categories of this paper are: hep-ex
34
The categories of this paper are: chem-ph
31
The categories of this paper are: ao-sci
32
The categories of this paper are: atom-ph
7
The categories of this paper are: hep-th
14
The categories of this paper are: math-ph
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The categories of this paper are: q-fin
36
The categories of this paper are: cmp-lg
2
The categories of this paper are: math