Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Nanocomposite RE-Ba-Cu-O bulk superconductors   Nanocomposite oxide high-temperature bulk superconductors can be used as
quasi-magnets. Thanks to the recent progress of material processing,
quasi-magnet with 26 mm diameter can generate a large field of 17.6 T at 26 K.
These results are highly attractive for applications, involving levitation of
permanent magnets on the bulk superconductors. Indeed, several other
applications such as motors and magnetic resonance microscope using bulk
superconductors have been proposed and demonstrated. In this chapter, we
describe several techniques to improve the magnetic properties for bulk
superconductors together with some basics such as phase diagrams and
solidifications.

17
The categories of this paper are: q-fin
24
The categories of this paper are: dg-ga
13
The categories of this paper are: quant-ph
35
The categories of this paper are: mtrl-th
8
The categories of this paper are: hep-ex
33
The categories of this paper are: plasm-ph
26
The categories of this paper are: bayes-an
12
The categories of this paper are: nucl-th
3
The categories of this paper are: physics
37
The categories of this paper are: supr-con
22
The categories of this paper are: chao-dyn
10
The categories of this paper are: q-bio
32
The categories of this paper are: atom-ph
19
The categories of this paper are: eess
34
The categories of this paper are: chem-ph
11
The categories of this paper are: hep-lat