Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Quantum cloning a pair of orthogonally polarized photons with linear
  optics   A linear optical probabilistic scheme for the optimal cloning of a pair of
orthogonally-polarized photons is devised, based on single- and two-photon
interferences. It consists in a partial symmetrization device, realized with a
modified unbalanced Mach-Zehnder interferometer, followed by two independent
Hong-Ou-Mandel interferometers. This scheme has the advantage that it enables
quantum cloning without the need for stimulated amplification in a nonlinear
medium. It can also be modified so to make an optical two-qubit partial SWAP
gate, thereby providing a potentially useful tool to linear optics quantum
computing.

19
The categories of this paper are: eess
23
The categories of this paper are: solv-int
5
The categories of this paper are: gr-qc
1
The categories of this paper are: cs
34
The categories of this paper are: chem-ph
15
The categories of this paper are: nucl-ex
25
The categories of this paper are: patt-sol
30
The categories of this paper are: q-alg
37
The categories of this paper are: supr-con
16
The categories of this paper are: stat
32
The categories of this paper are: atom-ph
10
The categories of this paper are: q-bio
2
The categories of this paper are: math
11
The categories of this paper are: hep-lat
36
The categories of this paper are: cmp-lg
27
The categories of this paper are: comp-gas