Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Building partially entangled states with Grover's amplitude
  amplification process   We discuss how to build some partially entangled states of $n$ two-state
quantum systems (qubits). The optimal partially entangled state with a high
degree of symmetry is considered to be useful for overcoming a shot noise limit
of Ramsey spectroscopy under some decoherence. This state is invariant under
permutation of any two qubits and inversion between the ground state $|0\ket$
and an excited state $|1\ket$ for each qubit. We show that using selective
phase shifts in certain basis vectors and Grover's inversion about average
operations, we can construct this high symmetric entangled state by
$({polynomial in $n$})\times 2^{n/2}$ successive unitary transformations that
are applied on two or three qubits. We can apply our method to build more
general entangled states.

29
The categories of this paper are: funct-an
37
The categories of this paper are: supr-con
2
The categories of this paper are: math
16
The categories of this paper are: stat
10
The categories of this paper are: q-bio
17
The categories of this paper are: q-fin
32
The categories of this paper are: atom-ph
22
The categories of this paper are: chao-dyn
33
The categories of this paper are: plasm-ph
18
The categories of this paper are: econ
31
The categories of this paper are: ao-sci
28
The categories of this paper are: alg-geom
23
The categories of this paper are: solv-int
4
The categories of this paper are: cond-mat
24
The categories of this paper are: dg-ga
1
The categories of this paper are: cs