Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Competition between Spin Echo and Spin Self-Rephasing in a Trapped Atom
  Interferometer   We perform Ramsey interferometry on an ultracold 87Rb ensemble confined in an
optical dipoletrap. We use a \pi-pulse set at the middle of the interferometer
to restore the coherence of the spinensemble by canceling out phase
inhomogeneities and creating a spin echo in the contrast. However,for high
atomic densities, we observe the opposite behavior: the \pi-pulse accelerates
the dephasingof the spin ensemble leading to a faster contrast decay of the
interferometer. We understand thisphenomenon as a competition between the
spin-echo technique and an exchange-interaction drivenspin self-rephasing
mechanism based on the identical spin rotation effect. Our experimental data
iswell reproduced by a numerical model.

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The categories of this paper are: chem-ph
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The categories of this paper are: hep-lat
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The categories of this paper are: solv-int
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The categories of this paper are: eess
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The categories of this paper are: patt-sol
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The categories of this paper are: plasm-ph
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The categories of this paper are: comp-gas
12
The categories of this paper are: nucl-th
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The categories of this paper are: dg-ga
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The categories of this paper are: bayes-an
1
The categories of this paper are: cs
7
The categories of this paper are: hep-th
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The categories of this paper are: alg-geom
14
The categories of this paper are: math-ph
6
The categories of this paper are: astro-ph
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The categories of this paper are: ao-sci