Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Open and closed spin chains as multiprocessor wires: optimal engineering
  and reachability   We consider the perfect transfer of a state between arbitrary nodes of
one-dimensional spin-1/2 chain with optimally engineered couplings. Motivated
by the fact that such a system could be used as a data bus for connecting
multiple quantum processors, we derive two necessary and sufficient conditions
that have to be met in order to perfectly transfer a state between any two
nodes and we employ them to examine both open and closed geometries. Analytical
calculations and numerical optimizations are performed for both cases in order
to determine the reachability of certain target states and to provide optimal
values for the couplings which ensure perfect fidelity. An important finding is
that even-sized closed chains allow for perfect transfer between any pair of
sites and therefore are a promising platform for the implementation of data bus
protocols.

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The categories of this paper are: hep-th
32
The categories of this paper are: atom-ph
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The categories of this paper are: adap-org
16
The categories of this paper are: stat
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The categories of this paper are: chao-dyn
26
The categories of this paper are: bayes-an
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The categories of this paper are: solv-int
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The categories of this paper are: nucl-ex
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The categories of this paper are: alg-geom
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The categories of this paper are: funct-an
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The categories of this paper are: econ
34
The categories of this paper are: chem-ph
20
The categories of this paper are: acc-phys
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The categories of this paper are: plasm-ph
4
The categories of this paper are: cond-mat
25
The categories of this paper are: patt-sol