Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Quantum correlations by four-wave-mixing in atomic vapor. Theory and
  Experiments   We study both theoretically and experimentally the generation of quantum
correlations in the continuous variable regime by way of four-wave mixing in a
hot atomic vapor. Two theoretical approaches have been developed. On one side,
we study the four-wave mixing under the "classical" non-linear optics point of
view. In such a way we obtain the evolution equation for an ideal linear
amplifier in a {\chi}^(3) medium. On the other side, we present a microscopic
model with 4 levels in the double-{\Lambda} configuration to calculate the
{\chi}^(3) coefficient in a atomic vapor dressed with a laser. This calculation
allows us to derive the spectra of intensity noise for interesting parameters.
The experimental part of this work describes the demonstration of this effect
on the D1 line of rubidium 85. We present a measurement of relative intensity
squeezing as high as -9.2dB below the standard quantum limit, and an original
regime where quantum correlations have been measured without
amplification.These results have broad applications in the field of multimode
quantum optics, e.g. quantum imaging or the multimode quantum memories.

12
The categories of this paper are: nucl-th
16
The categories of this paper are: stat
36
The categories of this paper are: cmp-lg
1
The categories of this paper are: cs
9
The categories of this paper are: nlin
4
The categories of this paper are: cond-mat
2
The categories of this paper are: math
14
The categories of this paper are: math-ph
5
The categories of this paper are: gr-qc
27
The categories of this paper are: comp-gas
33
The categories of this paper are: plasm-ph
31
The categories of this paper are: ao-sci
8
The categories of this paper are: hep-ex
32
The categories of this paper are: atom-ph
24
The categories of this paper are: dg-ga
22
The categories of this paper are: chao-dyn