Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: On the melting of the nanocrystalline vortex matter in high-temperature
  superconductors   Multilevel Monte Carlo simulations of the vortex matter in the
highly-anisotropic high-temperature superconductor Bi$_2$Sr$_2$CaCu$_2$O$_8$
were performed. We introduced low concentration of columnar defects satisfying
$B_\phi\le B$. Both the electromagnetic and Josephson interactions among
pancake vortices were included. The nanocrystalline, nanoliquid and homogeneous
liquid phases were identified in agreement with experiments. We observed the
two-step melting process and also noted an enhancement of the structure factor
just prior to the melting transition. A proposed theoretical model is in
agreement with our findings.

32
The categories of this paper are: atom-ph
29
The categories of this paper are: funct-an
8
The categories of this paper are: hep-ex
7
The categories of this paper are: hep-th
20
The categories of this paper are: acc-phys
16
The categories of this paper are: stat
15
The categories of this paper are: nucl-ex
6
The categories of this paper are: astro-ph
37
The categories of this paper are: supr-con
11
The categories of this paper are: hep-lat
5
The categories of this paper are: gr-qc
35
The categories of this paper are: mtrl-th
33
The categories of this paper are: plasm-ph
2
The categories of this paper are: math
28
The categories of this paper are: alg-geom
26
The categories of this paper are: bayes-an