Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Spin-charge-density wave in a squircle-like Fermi surface for ultracold
  atoms   We derive and discuss an experimentally realistic model describing ultracold
atoms in an optical lattice including a commensurate, but staggered, Zeeman
field. The resulting band structure is quite exotic; fermions in the third band
have an unusual rounded picture-frame Fermi surface (essentially two concentric
squircles), leading to imperfect nesting. We develop a generalized
SO(3,1)xSO(3,1) theory describing the spin and charge degrees of freedom
simultaneously, and show that the system can develop a coupled
spin-charge-density wave order. This ordering is absent in studies of the
Hubbard model that treat spin and charge density separately.

27
The categories of this paper are: comp-gas
32
The categories of this paper are: atom-ph
12
The categories of this paper are: nucl-th
0
The categories of this paper are: hep-ph
23
The categories of this paper are: solv-int
31
The categories of this paper are: ao-sci
8
The categories of this paper are: hep-ex
36
The categories of this paper are: cmp-lg
13
The categories of this paper are: quant-ph
11
The categories of this paper are: hep-lat
5
The categories of this paper are: gr-qc
24
The categories of this paper are: dg-ga
9
The categories of this paper are: nlin
6
The categories of this paper are: astro-ph
10
The categories of this paper are: q-bio
21
The categories of this paper are: adap-org