Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Determination of the quantized topological magneto-electric effect in
  topological insulators from Rayleigh scattering   Topological insulators (TIs) exhibit many exotic properties. In particular, a
topological magneto-electric (TME) effect, quantized in units of the fine
structure constant, exists in TIs. In this Letter, we study theoretically the
scattering properties of electromagnetic waves by TI circular cylinders
particularly in the Rayleigh scattering limit. Compared with ordinary
dielectric cylinders, the scattering by TI cylinders shows many unusual
features due to the TME effect. Two proposals are suggested to determine the
TME effect of TIs simply based on measuring the electric-field components of
scattered waves in the far field at one or two scattering angles. Our results
could also offer a way to measure the fine structure constant.

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The categories of this paper are: q-bio
20
The categories of this paper are: acc-phys
1
The categories of this paper are: cs
26
The categories of this paper are: bayes-an
21
The categories of this paper are: adap-org
27
The categories of this paper are: comp-gas
25
The categories of this paper are: patt-sol
14
The categories of this paper are: math-ph
36
The categories of this paper are: cmp-lg
28
The categories of this paper are: alg-geom
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The categories of this paper are: hep-ex
24
The categories of this paper are: dg-ga
9
The categories of this paper are: nlin
18
The categories of this paper are: econ
35
The categories of this paper are: mtrl-th
11
The categories of this paper are: hep-lat