Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Atomic memory based on recoil-induced resonances   In this work we perform a detailed theoretical and experimental investigation
of an atomic memory based on recoil-induced resonance in cold cesium atoms. We
consider the interaction of a nearly degenerated pump and probe beams with an
ensemble of two-level atoms. A full theoretical density matrix calculation in
the extended Hilbert space of the internal and external atomic degrees of
freedom allows us to obtain, from first principles, the transient and
stationary responses determining the probe transmission and the forward
four-wave mixing spectra. These two signals are generated together at the same
order of perturbation with respect to the intensities of pump and probe beams.
However, during continuous excitation of the sample, they are detected in very
different ways and the signal at the probe transmission appears to be
considerably larger, being the main focus of investigation prior to this work.
Moreover, we have investigated the storage of optical information in the atomic
external degrees of freedom, which provided a simple interpretation for the
previously-reported non-volatile character of this memory. The retrieved
signals after storage reveal the equivalent role of probe transmission and
four-wave mixing, as the two signals have similar amplitudes. Probe
transmission and forward four-wave-mixing spectra were then experimentally
measured for both continuous excitation and after storage. The experimental
observations are in good agreement with the developed theory and open a new
pathway for the reversible exchange of optical information with atomic systems.

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The categories of this paper are: q-bio
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The categories of this paper are: acc-phys
30
The categories of this paper are: q-alg
29
The categories of this paper are: funct-an
37
The categories of this paper are: supr-con
1
The categories of this paper are: cs
4
The categories of this paper are: cond-mat
23
The categories of this paper are: solv-int
36
The categories of this paper are: cmp-lg
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The categories of this paper are: hep-ex
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The categories of this paper are: nlin
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The categories of this paper are: physics
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The categories of this paper are: chem-ph
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The categories of this paper are: dg-ga
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The categories of this paper are: bayes-an
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The categories of this paper are: alg-geom