Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Spontaneous emission from a two-level atom in anisotropic one-band
  photonic crystals: a fractional calculus approach   Spontaneous emission (SE) from a two-level atom in a photonic crystal (PC)
with anisotropic one-band model is investigated using the fractional calculus.
Analytically solving the kinetic equation in terms of the fractional
exponential function, the dynamical discrepancy of SE between the anisotropic
and isotropic systems is discussed on the basis of different photon density of
states (DOS) and the existence of incoherent diffusion field that becomes even
more clearly as the atomic transition frequency lies close to the band edge.
With the same atom-field coupling strength and detuning in the forbidden gap,
the photon-atom bound states in the isotropic system turn into the unbound ones
in the anisotropic system that is consistent with the experimental observation
in $Phys.$ $Rev.$ $Lett.$ \textbf{96}, 243902 (2006). Dynamics along different
wavevectors with various curvatures of dispersion is also addressed with the
changes of the photon DOS and the appearance of the diffusion fields.

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The categories of this paper are: astro-ph
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The categories of this paper are: hep-ex
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The categories of this paper are: cmp-lg
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The categories of this paper are: stat
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The categories of this paper are: atom-ph
3
The categories of this paper are: physics
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The categories of this paper are: solv-int
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The categories of this paper are: eess
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The categories of this paper are: nucl-ex
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The categories of this paper are: chao-dyn
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The categories of this paper are: quant-ph
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The categories of this paper are: dg-ga
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The categories of this paper are: econ
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The categories of this paper are: math
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The categories of this paper are: alg-geom
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The categories of this paper are: funct-an