Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Orbital angular momentum coupling in elastic photon-photon scattering   In this letter, we investigate the effect of orbital angular momentum (OAM)
on elastic photon-photon scattering in vacuum for the first time. We define
exact solutions to the vacuum electro-magnetic wave equation which carry OAM.
Using those, the expected coupling between three initialwaves is derived in the
framework of an effective field theory based on the Euler-Heisenberg
La-grangian and shows that OAM adds a signature to the generated photons
thereby greatly improvingthe signal-to-noise ratio. This forms the basis for a
proposed high-power laser experiment utilizingquantum optics techniques to
filter the generated photons based on their OAM state

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The categories of this paper are: chao-dyn
33
The categories of this paper are: plasm-ph
9
The categories of this paper are: nlin
34
The categories of this paper are: chem-ph
10
The categories of this paper are: q-bio
7
The categories of this paper are: hep-th
12
The categories of this paper are: nucl-th
36
The categories of this paper are: cmp-lg
16
The categories of this paper are: stat
35
The categories of this paper are: mtrl-th
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The categories of this paper are: bayes-an
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The categories of this paper are: hep-lat
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The categories of this paper are: cond-mat
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The categories of this paper are: ao-sci
6
The categories of this paper are: astro-ph
14
The categories of this paper are: math-ph