Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Sub-cycle dynamics of electron-hole pairs and high-harmonic generation
  in bulk diamond subjected to intense femtosecond laser pulse   We present calculation of photoexcitation and high-harmonic generation in
bulk diamond induced by intense near-infrared laser pulse of photon energy 1.55
eV, time duration of 15 fs and peak field strength $F=$ 0.4 V/{\AA}. Depending
on the laser polarization direction, the pulsed irradiation creates
electron-hole pairs and transient density fluctuations in a localized region of
the crystal momentum space. As a consequence energetic inter- and intra-band
harmonics are generated with alternating phase during each half-cycle of the
driving pulse. The corresponding inter- and intra-band currents are in definite
phase relation with the laser pulse, reflecting the build-up of coherent
superposition of population between valence and conduction bands, and the
accelerated motion of charge carriers in their respective bands.

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The categories of this paper are: acc-phys
33
The categories of this paper are: plasm-ph
11
The categories of this paper are: hep-lat
27
The categories of this paper are: comp-gas
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The categories of this paper are: eess
1
The categories of this paper are: cs
15
The categories of this paper are: nucl-ex
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The categories of this paper are: funct-an
36
The categories of this paper are: cmp-lg
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The categories of this paper are: patt-sol
9
The categories of this paper are: nlin
37
The categories of this paper are: supr-con
35
The categories of this paper are: mtrl-th
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The categories of this paper are: dg-ga
14
The categories of this paper are: math-ph
22
The categories of this paper are: chao-dyn