Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Enhancement of the Critical Current Density of YBa2Cu3Ox Superconductors
  under Hydrostatic Pressure   The dependence of the critical current density Jc on hydrostatic pressure to
0.6 GPa is determined for a single 25-degree [001]-tilt grain boundary in a
bicrystalline ring of nearly optimally doped melt-textured YBa2Cu3Ox. Jc is
found to increase rapidly under pressure at +20 %/GPa. A new diagnostic method
is introduced (pressure-induced Jc relaxation) which reveals a sizeable
concentration of vacant oxygen sites in the grain boundary region. Completely
filling such sites with oxygen anions should lead to significant enhancements
in Jc.

18
The categories of this paper are: econ
12
The categories of this paper are: nucl-th
36
The categories of this paper are: cmp-lg
14
The categories of this paper are: math-ph
1
The categories of this paper are: cs
27
The categories of this paper are: comp-gas
8
The categories of this paper are: hep-ex
2
The categories of this paper are: math
22
The categories of this paper are: chao-dyn
0
The categories of this paper are: hep-ph
30
The categories of this paper are: q-alg
24
The categories of this paper are: dg-ga
35
The categories of this paper are: mtrl-th
34
The categories of this paper are: chem-ph
3
The categories of this paper are: physics
21
The categories of this paper are: adap-org