Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The effect of magnetic impurities in a two-band superconductor: A
  point-contact study of Mn-substituted MgB2 single crystals   We present the first results of directional point-contact measurements in
Mg_{1-x}Mn_{x}B_2 single crystals, with x up to 0.015 and bulk T_c down to 13.3
K. The order parameters Delta_{sigma} and Delta_{pi} were obtained by fitting
the conductance curves with the two-band Blonder-Tinkham-Klapwijk (BTK) model.
Both Delta_{pi} and Delta_{sigma} decrease with the critical temperature of the
junctions T_c^A, but remain clearly distinct up to the highest Mn content. Once
analyzed within the Eliashberg theory, the results indicate that spin-flip
scattering is dominant in the sigma band, as also confirmed by first-principle
band structure calculations.

33
The categories of this paper are: plasm-ph
24
The categories of this paper are: dg-ga
35
The categories of this paper are: mtrl-th
16
The categories of this paper are: stat
30
The categories of this paper are: q-alg
25
The categories of this paper are: patt-sol
20
The categories of this paper are: acc-phys
17
The categories of this paper are: q-fin
37
The categories of this paper are: supr-con
31
The categories of this paper are: ao-sci
8
The categories of this paper are: hep-ex
10
The categories of this paper are: q-bio
27
The categories of this paper are: comp-gas
22
The categories of this paper are: chao-dyn
6
The categories of this paper are: astro-ph
18
The categories of this paper are: econ