Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Realization of Dirac Point with Double Cones in Optics   The Dirac point with a double-cone structure for optical fields, an optical
analogy Dirac fermions in graphene, can be realized in optically homogenous
metamaterials. The condition for the realization of Dirac point in optical
systems is the varying of refractive index from negative to zero and then to
positive. Our analytical and numerical analysis have verified that, similar to
electrons in graphene, the light field near the Dirac point possesses of the
pseudodiffusive property, obeying the 1/L scaling law, where L is the
propagating distance of light inside the media.

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The categories of this paper are: hep-ex
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The categories of this paper are: math-ph
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The categories of this paper are: hep-th
9
The categories of this paper are: nlin
34
The categories of this paper are: chem-ph
31
The categories of this paper are: ao-sci
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The categories of this paper are: eess
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The categories of this paper are: gr-qc
33
The categories of this paper are: plasm-ph
26
The categories of this paper are: bayes-an
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The categories of this paper are: nucl-th
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The categories of this paper are: econ
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The categories of this paper are: alg-geom
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The categories of this paper are: q-alg
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The categories of this paper are: solv-int
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The categories of this paper are: chao-dyn