Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Proof of unconditional security of six-state quantum key distribution
  scheme   We prove the unconditional security of the standard six-state scheme for
quantum key distribution (QKD). We demonstrate its unconditional security up to
a bit error rate of 12.7 percents, by allowing only one-way classical
communications in the error correction/privacy amplification procedure between
Alice and Bob. This shows a clear advantage of the six-state scheme over
another standard scheme---BB84, which has been proven to be secure up to only
about 11 percents, if only one-way classical communications are allowed. Our
proof technique is a generalization of that of Shor-Preskill's proof of
security of BB84. We show that a advantage of the six-state scheme lies in the
Alice and Bob's ability to establish rigorously from their test sample the
non-trivial mutual information between the bit-flip and phase error patterns. A
modified version of the degenerate quantum codes studied by DiVincenzo, Shor
and Smolin is employed in our proof.

30
The categories of this paper are: q-alg
4
The categories of this paper are: cond-mat
15
The categories of this paper are: nucl-ex
2
The categories of this paper are: math
11
The categories of this paper are: hep-lat
33
The categories of this paper are: plasm-ph
10
The categories of this paper are: q-bio
5
The categories of this paper are: gr-qc
20
The categories of this paper are: acc-phys
16
The categories of this paper are: stat
3
The categories of this paper are: physics
31
The categories of this paper are: ao-sci
18
The categories of this paper are: econ
36
The categories of this paper are: cmp-lg
27
The categories of this paper are: comp-gas
23
The categories of this paper are: solv-int