Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Frustration effects in rapidly rotating square and triangular optical
  lattices   We discuss the ground state of the two-dimensional Bose-Hubbard (BH)
Hamiltonian, relevant for rotating gaseous Bose-Einstein condensates, by
employing \mathrm{U}\left(1\right) quantum rotor approach and the topologically
constrained path integral that includes a summation over
\mathrm{U}\left(1\right) topological charge. We derive an effective quantum
action for the BH model, which enables a non-perturbative treatment of the
zero-temperature phase transition. We calculate the ground-state phase diagram,
analytically deriving maximum repulsive energy for several rational values of
the frustration rotation parameter f=0, 1/2, 1/3, 1/4, and 1/6 for the square
and triangular lattice, which improves upon previous theoretical treatments.
The ground state of the rotating Bose-Einstein condensates on a triangular
lattice appears to be most stable against the effects of rotation. Performed
calculations revealed strong dependence of the critical ratio of the kinetic
energy to the repulsive on-site energy, that separates the global coherent from
the insulating state, on topology of the lattice.

25
The categories of this paper are: patt-sol
6
The categories of this paper are: astro-ph
33
The categories of this paper are: plasm-ph
17
The categories of this paper are: q-fin
36
The categories of this paper are: cmp-lg
29
The categories of this paper are: funct-an
0
The categories of this paper are: hep-ph
3
The categories of this paper are: physics
16
The categories of this paper are: stat
5
The categories of this paper are: gr-qc
2
The categories of this paper are: math
13
The categories of this paper are: quant-ph
26
The categories of this paper are: bayes-an
28
The categories of this paper are: alg-geom
20
The categories of this paper are: acc-phys
24
The categories of this paper are: dg-ga