Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Theory of Cherenkov radiation in periodic dielectric media: Emission
  spectrum   The Cherenkov radiation is substantially modified in the presence of a medium
with a nontrivial dispersion relation. We consider Cherenkov emission spectra
of a point charge moving in general three- (3D) and two-dimensional (2D)
photonic crystals. Exact analytical expressions for the spectral distribution
of the radiated power are obtained in terms of the Bloch mode expansion. The
resulting expression reduces to a simple contour integral (3D case) or a
one-dimensional sum (2D case) over a small fraction of the reciprocal space,
which is defined by the generalized Cherenkov condition. We apply our method to
a specific case of an electron moving with different velocities in a 2D
square-lattice photonic crystal. Our method demonstrates an excellent agreement
with numerically rigorous finite-difference time-domain calculations while
being less demanding on computational resources.

8
The categories of this paper are: hep-ex
29
The categories of this paper are: funct-an
26
The categories of this paper are: bayes-an
28
The categories of this paper are: alg-geom
36
The categories of this paper are: cmp-lg
6
The categories of this paper are: astro-ph
34
The categories of this paper are: chem-ph
16
The categories of this paper are: stat
19
The categories of this paper are: eess
33
The categories of this paper are: plasm-ph
35
The categories of this paper are: mtrl-th
10
The categories of this paper are: q-bio
4
The categories of this paper are: cond-mat
5
The categories of this paper are: gr-qc
18
The categories of this paper are: econ
32
The categories of this paper are: atom-ph