Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Universal scaling of Hall resistivity in clean and moderately clean
  limits for Hg- and Tl-based superconductors   The mixed-state Hall resistivity and the longitudinal resistivity in
HgBa_{2}CaCu_{2}O_{6}, HgBa_{2}Ca_{2}Cu_{3}O_{8}, and Tl_{2}Ba_{2}CaCu_{2}O_{8}
thin films have been investigated as functions of the magnetic field up to 18
T. We observe the universal scaling behavior between \rho_{xy} and \rho_{xx} in
the regions of the clean and the moderately clean limit. The scaling exponent
\beta is 1.9 in the clean limit at high field and low temperature whereas \beta
is 1.0 in the moderately clean limit at low field and high temperature,
consistent with a theory based on the midgap states in the vortex cores. This
finding implies that the Hall conductivity is also universal in Hg- and
Tl-based superconductors.

2
The categories of this paper are: math
17
The categories of this paper are: q-fin
10
The categories of this paper are: q-bio
36
The categories of this paper are: cmp-lg
13
The categories of this paper are: quant-ph
8
The categories of this paper are: hep-ex
37
The categories of this paper are: supr-con
6
The categories of this paper are: astro-ph
15
The categories of this paper are: nucl-ex
18
The categories of this paper are: econ
26
The categories of this paper are: bayes-an
20
The categories of this paper are: acc-phys
16
The categories of this paper are: stat
1
The categories of this paper are: cs
32
The categories of this paper are: atom-ph
31
The categories of this paper are: ao-sci