Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Squeezing of nonlinear spin observables by one axis twisting in the
  presence of decoherence: An analytical study   In an ensemble of two-level atoms that can be described in terms of a
collective spin, entangled states can be used to enhance the sensitivity of
interferometric precision measurements. While non-Gaussian spin states can
produce larger quantum enhancements than spin-squeezed Gaussian states, their
use requires the measurement of observables that are nonlinear functions of the
three components of the collective spin. In this paper we develop strategies
that achieve the optimal quantum enhancements using non-Gaussian states
produced by a nonlinear one-axis-twisting Hamiltonian, and show that
measurement-after-interaction techniques, known to amplify the output signals
in quantum parameter estimation protocols, are effective in measuring nonlinear
spin observables. Including the presence of the relevant decoherence processes
from atomic experiments, we determine analytically the quantum enhancement of
non-Gaussian over-squeezed states as a function of the noise parameters for
arbitrary atom numbers.

15
The categories of this paper are: nucl-ex
9
The categories of this paper are: nlin
24
The categories of this paper are: dg-ga
2
The categories of this paper are: math
26
The categories of this paper are: bayes-an
27
The categories of this paper are: comp-gas
32
The categories of this paper are: atom-ph
25
The categories of this paper are: patt-sol
22
The categories of this paper are: chao-dyn
14
The categories of this paper are: math-ph
20
The categories of this paper are: acc-phys
29
The categories of this paper are: funct-an
8
The categories of this paper are: hep-ex
30
The categories of this paper are: q-alg
5
The categories of this paper are: gr-qc
18
The categories of this paper are: econ