Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Ultranarrow-Band Photon Pair Source Compatible with Solid State Quantum
  Memories and Telecommunication Networks   We report on a source of ultranarrow-band photon pairs generated by widely
nondegenerate cavity-enhanced spontaneous down-conversion. The source is
designed to be compatible with Pr3+ solid state quantum memories and
telecommunication optical fibers, with signal and idler photons close to 606 nm
and 1436 nm, respectively. Both photons have a spectral bandwidth around 2 MHz,
matching the bandwidth of Pr3+ doped quantum memories. This source is ideally
suited for long distance quantum communication architectures involving solid
state quantum memories.

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The categories of this paper are: cmp-lg
4
The categories of this paper are: cond-mat
28
The categories of this paper are: alg-geom
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The categories of this paper are: eess
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The categories of this paper are: chao-dyn
12
The categories of this paper are: nucl-th
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The categories of this paper are: q-fin
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The categories of this paper are: nucl-ex
0
The categories of this paper are: hep-ph
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The categories of this paper are: adap-org
32
The categories of this paper are: atom-ph
3
The categories of this paper are: physics
11
The categories of this paper are: hep-lat
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The categories of this paper are: hep-th
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The categories of this paper are: bayes-an
10
The categories of this paper are: q-bio