Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Optimal ratio between phase basis and bit basis in QKD   In the original BB84 protocol, the bit basis and the phase basis are used
with equal probability. Lo et al (J. of Cryptology, 18, 133-165 (2005))
proposed to modify the ratio between the two bases by increasing the final key
generation rate. However, the optimum ratio has not been derived. In this
letter, in order to examine this problem, the ratio between the two bases is
optimized for exponential constraints given Eve's information
distinguishability and the final error probability.

2
The categories of this paper are: math
32
The categories of this paper are: atom-ph
20
The categories of this paper are: acc-phys
12
The categories of this paper are: nucl-th
15
The categories of this paper are: nucl-ex
10
The categories of this paper are: q-bio
1
The categories of this paper are: cs
19
The categories of this paper are: eess
25
The categories of this paper are: patt-sol
7
The categories of this paper are: hep-th
36
The categories of this paper are: cmp-lg
5
The categories of this paper are: gr-qc
24
The categories of this paper are: dg-ga
18
The categories of this paper are: econ
6
The categories of this paper are: astro-ph
22
The categories of this paper are: chao-dyn