Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Structure and ferromagnetic instability of the oxygen-deficient
  SrTiO$_3$ surface   SrTiO$_3$ (STO) is the substrate of choice to grow oxide thin-films and oxide
heterojunctions, which can form quasi-two-dimensional electronic phases that
exhibit a wealth of phenomena, and, thus, a workhorse in the emerging field of
metal-oxide electronics. Hence, it is of great importance to know the exact
character of the STO surface itself under various oxygen environments. Using
density functional theory within the spin generalized gradient approximation we
have investigated the structural, electronic and magnetic properties of the
oxygen-deficient STO surface. We find that the surface oxygen vacancies order
in periodic arrays giving rise to surface magnetic moments and a quasi
two-dimensional electron gas in the occupied Ti 3-d orbitals. The surface
confinement, the oxygen-vacancy ordering, and the octahedra distortions give
rise to spin-polarized $t_{2g}$ dispersive sub-bands; their energy split near
the Brillouin zone center acts as an effective Zeeman term, which, when we turn
on a Rashba interaction, produces bands with momentum-spin correlations similar
to those recently discovered on oxygen deficient STO surface.

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The categories of this paper are: adap-org
28
The categories of this paper are: alg-geom
23
The categories of this paper are: solv-int
33
The categories of this paper are: plasm-ph
8
The categories of this paper are: hep-ex
32
The categories of this paper are: atom-ph
6
The categories of this paper are: astro-ph
30
The categories of this paper are: q-alg
16
The categories of this paper are: stat
31
The categories of this paper are: ao-sci
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The categories of this paper are: math-ph
12
The categories of this paper are: nucl-th
37
The categories of this paper are: supr-con
0
The categories of this paper are: hep-ph
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The categories of this paper are: eess
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The categories of this paper are: hep-lat