Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Dynamic Pattern of Finite-Pulsed Beams inside One-dimensional Photonic
  Band Gap Materials   The dynamics of two-dimensional electromagnetic (EM) pulses through
one-dimensional photonic crystals (1DPC) has been theoretically studied.
Employing the time expectation integral over the Poynting vector as the arrival
time [Phys. Rev. Lett. 84, 2370, (2000)], we show that the superluminal
tunneling process of EM pulses is the propagation of the net forward-going
Poynting vector through the 1DPC, and the Hartman effect is due to the
saturation effect of the arrival time (smaller and smaller time accumulated) of
the net forward energy flow caused by the interference effect of the forward
and the backward field (from the interfaces of each layer) happened in the
region before the 1DPC and in the front part of the 1DPC.

18
The categories of this paper are: econ
10
The categories of this paper are: q-bio
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The categories of this paper are: alg-geom
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The categories of this paper are: nlin
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The categories of this paper are: math
8
The categories of this paper are: hep-ex
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The categories of this paper are: comp-gas
4
The categories of this paper are: cond-mat
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The categories of this paper are: ao-sci
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The categories of this paper are: q-alg
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The categories of this paper are: plasm-ph
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The categories of this paper are: dg-ga
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The categories of this paper are: bayes-an
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The categories of this paper are: hep-th
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The categories of this paper are: atom-ph
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The categories of this paper are: quant-ph