Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Pressure tuned superconductivity and normal state behavior in
  Ba(Fe$_{0.943}$Co$_{0.057}$)$_2$As$_2$ near the antiferromagnetic boundary   Superconductivity in iron pnictides is unconventional and pairing may be
mediated by magnetic fluctuations in the Fe-sublattice. Pressure is a clean
method to explore superconductivity in iron based superconductors by tuning the
ground state continuously without introducing disorder. Here we present a
systematic high pressure transport study in Ba(Fe$_{1-x}$Co$_{x}$)$_2$As$_2$
single crystals with $x=$ 0.057, which is near the antiferromagnetic
instability. Resistivity $\rho=\rho_0+AT^{n}$ was studied under applied
pressure up to 7.90 GPa. The parameter $n$ approaches a minimum value of
$n\approx 1$ at a critical pressure $P_c =$ 3.65 GPa. Near $P_c$, the
superconducting transition temperature $T_c$ reaches a maximum value of 25.8 K.
In addition, the superconducting diamagnetism at 2 K shows a sudden change
around the same critical pressure. These results may be associated with a
possible quantum critical point hidden inside the superconducting dome, near
optimum $T_c$.

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The categories of this paper are: hep-lat
12
The categories of this paper are: nucl-th
10
The categories of this paper are: q-bio
28
The categories of this paper are: alg-geom
35
The categories of this paper are: mtrl-th
25
The categories of this paper are: patt-sol
23
The categories of this paper are: solv-int
32
The categories of this paper are: atom-ph
19
The categories of this paper are: eess
9
The categories of this paper are: nlin
36
The categories of this paper are: cmp-lg
3
The categories of this paper are: physics
27
The categories of this paper are: comp-gas
5
The categories of this paper are: gr-qc
8
The categories of this paper are: hep-ex
26
The categories of this paper are: bayes-an