Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Analytic next-to-nearest neighbour XX models with perfect state transfer
  and fractional revival   Certain non-uniformly coupled spin chains can exhibit perfect transfer of
quantum states from end to end. Motivated by recent experimental
implementations, we extend the simplest such chain to next-to-nearest neighbour
(NNN) couplings. It is shown analytically that perfect state transfer can be
maintained under the extension and that end-to-end entanglement generation
(fractional revival) can occur.

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The categories of this paper are: stat
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The categories of this paper are: alg-geom
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The categories of this paper are: q-fin
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The categories of this paper are: chao-dyn
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The categories of this paper are: atom-ph
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The categories of this paper are: hep-lat
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The categories of this paper are: q-alg
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The categories of this paper are: hep-th
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The categories of this paper are: hep-ex
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The categories of this paper are: patt-sol
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The categories of this paper are: eess
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The categories of this paper are: bayes-an
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The categories of this paper are: econ
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The categories of this paper are: math
4
The categories of this paper are: cond-mat
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The categories of this paper are: chem-ph