Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Realization of a complete Stern-Gerlach interferometer: Towards a test
  of quantum gravity   The Stern-Gerlach effect, discovered a century ago, has become a paradigm of
quantum mechanics. Surprisingly there has been little evidence that the
original scheme with freely propagating atoms exposed to gradients from
macroscopic magnets is a fully coherent quantum process. Specifically, no
full-loop Stern-Gerlach interferometer has been realized with the scheme as
envisioned decades ago. Furthermore, several theoretical studies have explained
why such an interferometer is a formidable challenge. Here we provide a
detailed account of the first full-loop Stern-Gerlach interferometer
realization, based on highly accurate magnetic fields, originating from an atom
chip, that ensure coherent operation within strict constraints described by
previous theoretical analyses. Achieving this high level of control over
magnetic gradients is expected to facilitate technological as well as
fundamental applications, such as probing the interface of quantum mechanics
and gravity. While the experimental realization described here is for a single
atom, future challenges would benefit from utilizing macroscopic objects doped
with a single spin. Specifically, we show that such an experiment is in
principle feasible, opening the door to a new era of fundamental probes.

25
The categories of this paper are: patt-sol
27
The categories of this paper are: comp-gas
12
The categories of this paper are: nucl-th
0
The categories of this paper are: hep-ph
22
The categories of this paper are: chao-dyn
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The categories of this paper are: eess
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The categories of this paper are: alg-geom
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The categories of this paper are: solv-int
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The categories of this paper are: q-fin
33
The categories of this paper are: plasm-ph
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The categories of this paper are: econ
2
The categories of this paper are: math
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The categories of this paper are: math-ph
1
The categories of this paper are: cs
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The categories of this paper are: nucl-ex
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The categories of this paper are: nlin