Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Measurement of spectral functions of ultracold atoms in disordered
  potentials   We report on the measurement of the spectral functions of noninteracting
ultracold atoms in a three-dimensional disordered potential resulting from an
optical speckle field. Varying the disorder strength by 2 orders of magnitude,
we observe the crossover from the "quantum" perturbative regime of low disorder
to the "classical" regime at higher disorder strength, and find an excellent
agreement with numerical simulations. The method relies on the use of
state-dependent disorder and the controlled transfer of atoms to create
well-defined energy states. This opens new avenues for experimental
investigations of three-dimensional Anderson localization.

7
The categories of this paper are: hep-th
16
The categories of this paper are: stat
6
The categories of this paper are: astro-ph
21
The categories of this paper are: adap-org
29
The categories of this paper are: funct-an
25
The categories of this paper are: patt-sol
11
The categories of this paper are: hep-lat
2
The categories of this paper are: math
3
The categories of this paper are: physics
37
The categories of this paper are: supr-con
23
The categories of this paper are: solv-int
17
The categories of this paper are: q-fin
24
The categories of this paper are: dg-ga
0
The categories of this paper are: hep-ph
14
The categories of this paper are: math-ph
36
The categories of this paper are: cmp-lg