Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Quantum computation over the butterfly network   In order to investigate distributed quantum computation under restricted
network resources, we introduce a quantum computation task over the butterfly
network where both quantum and classical communications are limited. We
consider deterministically performing a two-qubit global unitary operation on
two unknown inputs given at different nodes, with outputs at two distinct
nodes. By using a particular resource setting introduced by M. Hayashi [Phys.
Rev. A \textbf{76}, 040301(R) (2007)], which is capable of performing a swap
operation by adding two maximally entangled qubits (ebits) between the two
input nodes, we show that unitary operations can be performed without adding
any entanglement resource, if and only if the unitary operations are locally
unitary equivalent to controlled unitary operations. Our protocol is optimal in
the sense that the unitary operations cannot be implemented if we relax the
specifications of any of the channels. We also construct protocols for
performing controlled traceless unitary operations with a 1-ebit resource and
for performing global Clifford operations with a 2-ebit resource.

26
The categories of this paper are: bayes-an
8
The categories of this paper are: hep-ex
33
The categories of this paper are: plasm-ph
22
The categories of this paper are: chao-dyn
28
The categories of this paper are: alg-geom
19
The categories of this paper are: eess
18
The categories of this paper are: econ
36
The categories of this paper are: cmp-lg
35
The categories of this paper are: mtrl-th
3
The categories of this paper are: physics
15
The categories of this paper are: nucl-ex
11
The categories of this paper are: hep-lat
20
The categories of this paper are: acc-phys
4
The categories of this paper are: cond-mat
1
The categories of this paper are: cs
23
The categories of this paper are: solv-int