Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: An Entanglement Filter   The ability to filter quantum states is a key capability in quantum
information science and technology, in which one-qubit filters, or polarizers,
have found wide application. Filtering on the basis of entanglement requires
extension to multi-qubit filters with qubit-qubit interactions. We demonstrated
an optical entanglement filter that passes a pair of photons if they have the
desired correlations of their polarization. Such devices have many important
applications to quantum technologies.

24
The categories of this paper are: dg-ga
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The categories of this paper are: adap-org
18
The categories of this paper are: econ
8
The categories of this paper are: hep-ex
27
The categories of this paper are: comp-gas
19
The categories of this paper are: eess
37
The categories of this paper are: supr-con
22
The categories of this paper are: chao-dyn
3
The categories of this paper are: physics
26
The categories of this paper are: bayes-an
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The categories of this paper are: nucl-ex
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The categories of this paper are: patt-sol
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The categories of this paper are: astro-ph
33
The categories of this paper are: plasm-ph
1
The categories of this paper are: cs
32
The categories of this paper are: atom-ph