Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Quantum states characterization for the zero-error capacity   The zero-error capacity of quantum channels was defined as the least upper
bound of rates at which classical information can be transmitted through a
quantum channel with probability of error equal to zero. This paper
investigates some properties of input states and measurements used to attain
the quantum zero-error capacity. We start by reformulating the problem of
finding the zero-error capacity in the language of graph theory. This
alternative definition is used to prove that the zero-error capacity of any
quantum channel can be reached by using tensor products of pure states as
channel inputs, and projective measurements in the channel output. We conclude
by presenting an example that illustrates our results.

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The categories of this paper are: cond-mat
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The categories of this paper are: patt-sol
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The categories of this paper are: astro-ph
30
The categories of this paper are: q-alg
33
The categories of this paper are: plasm-ph
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: nlin
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The categories of this paper are: hep-th
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The categories of this paper are: gr-qc
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The categories of this paper are: acc-phys
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The categories of this paper are: atom-ph
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The categories of this paper are: chem-ph
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The categories of this paper are: solv-int
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The categories of this paper are: supr-con
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The categories of this paper are: econ