Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A Note on Quantum Key Channel Efficiency and Security using Correlated
  Photon Beam Transmitters   Quantum-correlated photon sources provide a means of suppressing multiple
photon emission and thus improving the security and efficiency of quasi
single-photon quantum key distribution systems. We present illustrative
photon-counting statistics for a Poissonian source conditioned by photon number
measurements on a fully correlated twin beam with a non-ideal photon counter.
We show that high photon counting efficiency is needed to obtain significant
improvement in channel efficiency (bits per symbol) and/or security (in the
form of reduced Shannon entropy leakage) over a single beam source.

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The categories of this paper are: physics
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The categories of this paper are: math-ph
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The categories of this paper are: mtrl-th
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The categories of this paper are: cond-mat
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The categories of this paper are: chem-ph
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The categories of this paper are: hep-ex
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The categories of this paper are: nlin
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The categories of this paper are: patt-sol
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The categories of this paper are: atom-ph
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The categories of this paper are: q-alg
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The categories of this paper are: stat
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The categories of this paper are: adap-org
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The categories of this paper are: comp-gas
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The categories of this paper are: chao-dyn
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The categories of this paper are: acc-phys
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The categories of this paper are: astro-ph