Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: From Quantum Field Theory to Nano-Optics : Refractive Properties of
  Graphene in a Medium-Strong Magnetic field   1-loop quantum corrections are shown to induce large effects on the
refraction index n inside a graphene strip in the presence of an external
magnetic field B orthogonal to it. To this purpose, we use the tools of Quantum
Field Theory to calculate the photon propagator at 1-loop inside graphene in
position space, which leads to an effective vacuum polarization in a brane-like
theory of photons interacting with massless electrons at locations confined
inside the thin strip (its longitudinal spread is considered to be infinite).
The effects factorize into quantum ones, controlled by the value of B and that
of the electromagnetic coupling alpha, and a "transmittance function" U in
which the geometry of the sample and the resulting confinement of electrons
play the major roles. We consider photons inside the visible spectrum and
magnetic fields in the range 1-20 Teslas. At B=0, quantum effects depend very
weakly on alpha and n is essentially controlled by U; we recover, then, an
opacity for visible light of the same order of magnitude pi * alpha_{vac} as
measured experimentally.

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The categories of this paper are: hep-th
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The categories of this paper are: acc-phys
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The categories of this paper are: cond-mat
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The categories of this paper are: econ
29
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: hep-ex
22
The categories of this paper are: chao-dyn
28
The categories of this paper are: alg-geom
37
The categories of this paper are: supr-con
21
The categories of this paper are: adap-org
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The categories of this paper are: eess
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The categories of this paper are: patt-sol
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The categories of this paper are: q-bio
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The categories of this paper are: comp-gas
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The categories of this paper are: ao-sci