Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Spatial interference of coherent atomic waves by manipulation of the
  internal quantum state   A trapped 87Rb Bose-Einstein condensate is initially put into a superposition
of two internal states. Under the effect of gravity and by means of a second
transition, we prepare two vertically displaced condensates in the same
internal state. These constitute two coherent sources of matter waves with
adjustable spatial separation. Fringe patterns, observed after free expansion,
are associated with the interplay between internal and external degrees of
freedom and substantially agree with those for a double slit experiment.

7
The categories of this paper are: hep-th
36
The categories of this paper are: cmp-lg
23
The categories of this paper are: solv-int
15
The categories of this paper are: nucl-ex
8
The categories of this paper are: hep-ex
1
The categories of this paper are: cs
34
The categories of this paper are: chem-ph
22
The categories of this paper are: chao-dyn
12
The categories of this paper are: nucl-th
33
The categories of this paper are: plasm-ph
21
The categories of this paper are: adap-org
13
The categories of this paper are: quant-ph
24
The categories of this paper are: dg-ga
27
The categories of this paper are: comp-gas
9
The categories of this paper are: nlin
3
The categories of this paper are: physics