Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: High Harmonic Generation in SF$_{6}$: Raman-excited Vibrational Quantum
  Beats   In a recent experiment (N. Wagner et al., PNAS v103, p13279) on SF$_{6}$, a
high-harmonic generating laser pulse is preceded by a pump pulse which
stimulates Raman-active modes in the molecule. Varying the time delay between
the two pulses modulates high harmonic intensity, with frequencies equal to the
vibration frequencies of the Raman-active modes. We propose an explanation of
this modulation as a quantum interference between competing pathways that occur
via adjacent vibrational states of the molecule. The Raman and high harmonic
processes act as beamsplitters, producing vibrational quantum beats among the
Raman-active vibrational modes that are excited by the first pulse. We
introduce a rigorous treatment of the electron-ion recombination process and
the effect of the ionic Coulomb field in the electron propagation outside the
molecule, improving over the widely-used three-step model.

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The categories of this paper are: adap-org
5
The categories of this paper are: gr-qc
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The categories of this paper are: stat
2
The categories of this paper are: math
28
The categories of this paper are: alg-geom
4
The categories of this paper are: cond-mat
6
The categories of this paper are: astro-ph
36
The categories of this paper are: cmp-lg
30
The categories of this paper are: q-alg
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The categories of this paper are: dg-ga
15
The categories of this paper are: nucl-ex
1
The categories of this paper are: cs
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The categories of this paper are: nlin
8
The categories of this paper are: hep-ex
31
The categories of this paper are: ao-sci
32
The categories of this paper are: atom-ph