Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A magnetic lens for cold atoms controlled by a rf field   We report on a new type of magnetic lens that focuses atomic clouds using a
static inhomogeneous magnetic field in combination with a radio-frequency
field. The experimental study is performed with a cloud of cold cesium atoms.
The rf field adiabatically deforms the magnetic potential of a coil and
therefore changes its focusing properties. The focal length can be tuned
precisely by changing the rf frequency value. Depending on the rf antenna
position relative to the DC magnetic profile, the focal length of the atomic
lens can be either decreased or increased by the rf field.

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The categories of this paper are: hep-ex
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The categories of this paper are: acc-phys
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The categories of this paper are: astro-ph
27
The categories of this paper are: comp-gas
11
The categories of this paper are: hep-lat
25
The categories of this paper are: patt-sol
12
The categories of this paper are: nucl-th
31
The categories of this paper are: ao-sci
13
The categories of this paper are: quant-ph
34
The categories of this paper are: chem-ph
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The categories of this paper are: nlin
5
The categories of this paper are: gr-qc
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The categories of this paper are: cs
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The categories of this paper are: chao-dyn
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The categories of this paper are: nucl-ex
14
The categories of this paper are: math-ph