Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Nonlinear tunneling of BEC in an optical lattice: signatures of quantum
  collapse and revival   Quantum theory of the intraband resonant tunneling of a Bose-Einstein
condensate loaded in a twodimensional optical lattice is considered. It is
shown that the phenomena of quantum collapse and revival can be observed in the
fully quantum problem. The mean-field limit of the theory is analyzed using the
WKB approximation for discrete equations, establishing in this way a direct
connection between the two approaches conventionally used in very different
physical contexts. More specifically we show that there exist two different
regimes of tunneling and study dependence of quantum collapse and revival on
the number of condensed atoms.

29
The categories of this paper are: funct-an
15
The categories of this paper are: nucl-ex
31
The categories of this paper are: ao-sci
37
The categories of this paper are: supr-con
10
The categories of this paper are: q-bio
3
The categories of this paper are: physics
14
The categories of this paper are: math-ph
9
The categories of this paper are: nlin
2
The categories of this paper are: math
34
The categories of this paper are: chem-ph
28
The categories of this paper are: alg-geom
25
The categories of this paper are: patt-sol
21
The categories of this paper are: adap-org
17
The categories of this paper are: q-fin
12
The categories of this paper are: nucl-th
32
The categories of this paper are: atom-ph