Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Asymptotic performance of optimal state estimation in quantum two level
  system   We derived an asymptotic bound the accuracy of the estimation when we use the
quantum correlation in the measuring apparatus. It is also proved that this
bound can be achieved in any model in the quantum two-level system. Moreover,
we show that this bound of such a model cannot be attained by any quantum
measurement with no quantum correlation in the measuring apparatus. That is, in
such a model, the quantum correlation can improve the accuracy of the
estimation in an asymptotic setting.

35
The categories of this paper are: mtrl-th
22
The categories of this paper are: chao-dyn
5
The categories of this paper are: gr-qc
30
The categories of this paper are: q-alg
28
The categories of this paper are: alg-geom
26
The categories of this paper are: bayes-an
7
The categories of this paper are: hep-th
10
The categories of this paper are: q-bio
37
The categories of this paper are: supr-con
29
The categories of this paper are: funct-an
32
The categories of this paper are: atom-ph
20
The categories of this paper are: acc-phys
9
The categories of this paper are: nlin
8
The categories of this paper are: hep-ex
17
The categories of this paper are: q-fin
2
The categories of this paper are: math