Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Long distance entanglement swapping with photons from separated sources   We report the first experimental realization of entanglement swapping over
large distances in optical fibers. Two photons separated by more than two km of
optical fibers are entangled, although they never directly interacted. We use
two pairs of time-bin entangled qubits created in spatially separated sources
and carried by photons at telecommunication wavelengths. A partial Bell state
measurement is performed with one photon from each pair which projects the two
remaining photons, formerly independent onto an entangled state. A visibility
high enough to violate a Bell inequality is reported, after both photons have
each travelled through 1.1 km of optical fiber.

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The categories of this paper are: solv-int
36
The categories of this paper are: cmp-lg
32
The categories of this paper are: atom-ph
25
The categories of this paper are: patt-sol
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The categories of this paper are: ao-sci
34
The categories of this paper are: chem-ph
30
The categories of this paper are: q-alg
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The categories of this paper are: eess
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The categories of this paper are: hep-th
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The categories of this paper are: chao-dyn
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The categories of this paper are: comp-gas
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The categories of this paper are: alg-geom
33
The categories of this paper are: plasm-ph
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The categories of this paper are: astro-ph
10
The categories of this paper are: q-bio
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The categories of this paper are: adap-org