Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Absence of Hole Confinement in Transition Metal Oxides with Orbital
  Degeneracy   We investigate the spectral properties of a hole moving in a two-dimensional
Hubbard model for strongly correlated t_2g electrons. Although superexchange
interactions are Ising-like, a quasi-one-dimensional coherent hole motion
arises due to effective three-site terms. This mechanism is fundamentally
different from the hole motion via quantum fluctuations in the conventional
spin model with SU(2) symmetry. The orbital model describes also propagation of
a hole in some e_g compounds, and we argue that orbital degeneracy alone does
not lead to hole self-localization.

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The categories of this paper are: alg-geom
10
The categories of this paper are: q-bio
30
The categories of this paper are: q-alg
29
The categories of this paper are: funct-an
16
The categories of this paper are: stat
19
The categories of this paper are: eess
3
The categories of this paper are: physics
5
The categories of this paper are: gr-qc
1
The categories of this paper are: cs
18
The categories of this paper are: econ
23
The categories of this paper are: solv-int
36
The categories of this paper are: cmp-lg
22
The categories of this paper are: chao-dyn
2
The categories of this paper are: math
20
The categories of this paper are: acc-phys
27
The categories of this paper are: comp-gas